DETECTING DEVICE

A detecting device detecting an operation of a detection object may include a movable member that may move in association with the operation of the detection object, a fixing member that may movably support the movable member, a single magnet that may be disposed in the movable member and in which an N pole and an S pole may line in a movement direction of the movable member, and a single magnetic sensor disposed in the fixing member. The magnetic sensor may be arranged to be opposed to the magnet on a movement track of the magnet as viewed in a direction perpendicular to the movement direction of the movable member.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 USC 119 from Japanese Patent Application No. 071194/2019 filed on Apr. 3, 2019, the disclosure of which is incorporated by reference herein.

TECHNICAL FIELD

The present invention relates to a detecting device.

BACKGROUND

Japanese Patent No. 4650796 discloses a detecting device (a range detection device) that is used for detection of a selection range in an automatic transmission.

The detecting device disclosed in Japanese Patent No. 4650796 includes a movable member that moves in association with a switch of the selection range and a fixing member that movably supports the movable member.

A plurality of magnets are disposed in the inside of the movable member. In the movable member, the plurality of magnets line to be spaced from each other in a direction perpendicular to a movement direction of the movable member. N poles and S poles alternately line in the movement direction of the movable member in each of the magnets.

The fixing member is provided with a plurality of HALL ICs (magnetic sensors). The HALL ICs are disposed as many as the magnets in a one magnet-to-one HALL IC relation.

In the detecting device, when the movable member moves in association with the switch of the selection range, the selection range is determined based upon a magnetic force detected by each of the HALL ICs.

The HALL ICs as many as the magnets are required in the detecting device. Therefore, a manufacturing cost of the detecting device gets high.

Therefore, it is required to provide a detecting device of a less expensive structure.

SUMMARY

Accordingly, the present invention is made in view of the above-described problem in the conventional technology, and an object of the present invention is to provide a detecting device of a less expensive structure.

A detecting device detecting an operation of a detection object according to the present invention, comprises:

a movable member that moves in association with the operation of the detection object;

a fixing member that movably supports the movable member;

a single magnet that is disposed in the movable member and in which an N pole and an S pole line in a movement direction of the movable member; and

a single magnetic sensor disposed in the fixing member, wherein

the magnetic sensor is arranged to be opposed to the magnet on a movement track of the magnet as viewed in a direction perpendicular to the movement direction of the movable member.

According to the present invention, it is possible to provide the detecting device less expensively.

DETAILED DESCRIPTION

Hereinafter, a detecting device according to an embodiment in the present invention will be explained with reference to the accompanying drawings.

FIG. 1is an exploded perspective view illustrating a detecting device1. InFIG. 1, a magnet6is arranged outside of a movable member5for explaining a shape of the magnet6embedded in the inside of the movable member5

In the following explanation, a positional relation of respective components in the detecting device1will be explained on a basis of an upper-lower direction inFIG. 1for descriptive purposes.

The detecting device1is disposed in a transmission case of an automatic transmission, for example, and outputs a signal for determining a selection range in the automatic transmission.

The detecting device1is formed by assembling a pole board2fixed on the transmission case of the automatic transmission, a hub3supported by a support hole22of the pole board2to be rotatable therein, a detent plate4rotating together with the hub3and a movable member5rotating together with the detent plate4in a rotation axis X direction.

FIG. 4is a plan view illustrating the pole board2from the upper side in the detent plate4-side. However, the detent plate4is omitted in illustration ofFIG. 4.

As illustrated inFIG. 4, the pole board2has a plate-shaped base portion21formed in an approximate fan shape as viewed in the rotation axis X direction. The base portion21is provided with the support hole22formed in a section corresponding to a fan top of the fan shape to support the hub3.

As illustrated inFIG. 3A, the support hole22is disposed to penetrate through the base portion21in a thickness direction (the rotation axis X direction).

A tubular wall23surrounding the support hole22is disposed on a top surface21aof the base portion21in the detent plate4-side. The tubular wall23projects to the upward side in the detent plate4-side from the base portion21. A top end23aof the tubular wall23is formed as a flat surface perpendicular to the rotation axis X and supports a bottom surface4bof the detent plate4.

As illustrated inFIG. 4, a groove24is formed on an outer diameter side of the tubular wall23to surround the outer periphery of the tubular wall23at a predetermined interval. The groove24is formed in an arc shape having a predetermined width W1in a radial direction of the rotation axis X as viewed in the rotation axis X direction.

As illustrated inFIG. 3A, the groove24opens on the top surface21aof the base portion21in the detent plate4-side.

As illustrated inFIG. 4, one end24aand the other end24bof the groove24in the longitudinal direction open to one side surface21cand the other side surface21dof the base portion21in the circumferential direction around the rotation axis X.

As shown inFIG. 3A, an accommodation portion25of a printed board7is disposed on a bottom surface21bof the base portion21in a position at the opposite side of the groove24in the rotation axis X direction.

As illustrated inFIG. 2A, the accommodation portion25has a tubular wall251surrounding the outer periphery of the printed board7. The accommodation portion25opens to the bottom surface21b-side of the base portion21and an opening of the accommodation portion25is sealed by a sealing member255.

As illustrated inFIG. 3A, a support portion252for supporting the printed board7is disposed in the inside of the tubular wall251. The support portion252is disposed along the inner periphery of the tubular wall251, and a space Sa is formed inside of the support portion252to avoid interference with a magnetic sensor75(refer toFIG. 3B) mounted on the printed board7.

An area between the space Sa and the above-mentioned groove24is formed as a thin portion241a thickness of which is thin in the rotation axis X direction.

As illustrated inFIG. 4, a rib26is disposed in the outer diameter side of the groove24to surround the outer periphery of the tubular wall23at a predetermined interval. The rib26is formed in an arc shape having a predetermined width W2in a radial direction of the rotation axis X as viewed in the rotation axis X direction.

As illustrated inFIG. 3A, the rib26projects upward in the detent plate4-side from the base portion21. A top end26aof the rib26is formed as a flat surface perpendicular to the rotation axis X and supports a bottom surface4bof the detent plate4.

As illustrated inFIG. 4, in the base portion21, a connector portion27and a connection portion28to a fixation-side member are disposed on the outer diameter side of the rib26. The connector portion27and the connection portion28are arranged to be spaced from each other in the circumferential direction around the rotation axis X.

One end of a connection terminal extending from the printed board7is exposed to the inside of the connector portion27.

The connection portion28is provided with an engaging groove281on an approximately central part thereof in the circumferential direction (a left-right direction in the figure) around the rotation axis X to open to the outer periphery side. A fixing member90in the transmission case side is inserted in the engaging groove281at the time of fixing the detecting device1in the inside of the transmission case, thus fixing a positional relation between the detecting device1and the transmission case.

The connection portion28is provided with a first support portion285in a position adjacent to the engaging groove281.

As illustrated inFIG. 3B, the first support portion285is a band-shaped member that extends from the lower side to the upper side on the outer peripheral side of the detent plate4and further, extends to the rotation axis X-side. An abutting portion285aabutting on the top surface4aof the detent plate4projects downward to the detent plate4-side at the tip end of the first support portion285.

In the detecting device1, the first support portion285is disposed to support the top surface4aof the detent plate4.

As illustrated inFIG. 4, the base portion21of the pole board2is provided with a swollen portion29near the tubular wall23. The swollen portion29is swollen in a direction away from the rotation axis X and in a direction away from the connection portion28.

The swollen portion29is provided with a second support portion295disposed in a position at the opposite side to the first support portion285across the rotation axis X.

As illustrated inFIG. 3A, the second support portion295is a band-shaped member that extends from the lower side to the upper side on the outer peripheral side of the detent plate4and further, extends to the rotation axis X-side.

An abutting portion295aabutting on the top surface4aof the detent plate4projects downward to the detent plate4-side at the tip end of the second support portion295.

In the detecting device1, the second support portion295is disposed to support the top surface4aof the detent plate4.

FIG. 5Ais a perspective view illustrating the hub3as viewed from an oblique upper side, andFIG. 5Bis a cross section illustrating the hub3, taken on plane A inFIG. 5A, as viewed from the upper side.

As illustrated inFIG. 3A, the hub3supported by the support hole22of the pole board2to be rotatable therein is disposed along the rotation axis X.

As illustrated inFIG. 5A, the hub3is provided with a tubular base portion31having a through hole310in which an unillustrated manual shaft is attached.

The base portion31is provided with a large diameter portion32at an approximately central part thereof in the rotation axis X direction. The large diameter portion32is formed with an outer dimeter substantially matched to an inner diameter of the support hole22(refer toFIG. 3A) on the pole board2-side.

As illustrated inFIG. 5B, the large diameter portion32is provided with flat portions321,321(width across flat portion).

The flat portions321,321(width across flat portion) are formed by cutting the outer periphery of the large diameter portion32along straight lines Ln, Ln in parallel to a diameter line Lm of the hub3as viewed in the rotation axis X direction.

The flat portions321,321are disposed in parallel to each other in a positional relation of being symmetrical across the rotation axis X as viewed in the rotation axis X direction.

As illustrated inFIG. 5A, the large diameter portion32is provided with the flat portions321,321toward the upper side from an approximately middle part in the rotation axis X direction. Therefore, in the hub3the flat portions321,321are disposed over the large diameter portion32and the base portion31positioned on the upper side of the large diameter portion32.

The large diameter portion32is provided with stopper portions322in a region closer to the upper side than bottom sides321a,321aof the flat portions321,321. The stopper portions322comprise four portions that are disposed at equal intervals in the circumferential direction around the rotation axis X as viewed in the rotation axis X direction.

The stopper portions322abut on the top surface4aof the detent plate4in the rotation axis X direction when the detent plate4is attached to the large diameter portion32(refer toFIG. 3B).

FIG. 6is a plan view illustrating the detent plate4as viewed from the upper side in the detent plate4-side.

The detent plate4has a plate-shaped base portion41formed in an approximate fan shape as viewed in the rotation axis X direction.

The base portion41is provided with a through hole42in a section corresponding to a fan top in the fan shape of the base portion41.

The through hole42is provided with flat portions421,421(width across flat portion) in parallel to each other in a positional relation of being symmetrical across the rotation axis X. The detent plate4is attached to the hub3to be incapable of relatively rotating thereto with the engagement of the flat portions421,421to the above-mentioned flat portions321,321(width across flat portion) of the hub3.

The base portion41is provided with a plurality of recessed portions45(45ato45e) recessed to the rotation axis side in a section corresponding to a fan end in the fan shape of the base portion41.

The detent plate4turns around the rotation axis X at the time of switching the selection range in the automatic transmission.

When the selection range in the automatic transmission is in a parking position, an engaging piece91of a detent spring (unillustrated) is elastically engaged to the recessed portion45a. When the selection range in the automatic transmission is in a neutral position, the engaging piece91of the detent spring (unillustrated) is elastically engaged to the recessed portion45c. When the selection range in the automatic transmission is in a low position, the engaging piece91of the detent spring (unillustrated) is elastically engaged to the recessed portion45e.

The engaging piece91of the detent spring (unillustrated) is disposed to retain an angular position of the detent plate4around the rotation axis X to a predetermined position corresponding to the selection range in the automatic transmission.

The detent plate4is provided with attachment holes43,43and attachment holes44,44for attaching the after-mentioned movable member5on the outer diameter side of the through hole42.

The attachment holes43,43and the attachment holes44,44penetrate through the base portion41of the detent plate4in a thickness direction (the rotation axis X direction).

As viewed in the rotation axis X direction, the attachment holes43,43are disposed to be spaced from each other on a virtual circle Ima surrounding the rotation axis X at a predetermined interval.

As viewed in the rotation axis X direction, the attachment holes44,44are disposed to be spaced from each other on a virtual circle Imb surrounding the rotation axis X at a predetermined interval.

The virtual circle Ima is a virtual circle with a diameter smaller than that of the virtual circle Imb. The attachment holes43,43in the rotation axis X-side are positioned in the circumferential direction around the rotation axis X between the attachment holes44,44adjacent to each other in the circumferential direction.

In the present embodiment, projections53,53in the movable member5-side are inserted in the attachment holes43,43for swage. Projections54,54in the movable member5-side are inserted in the attachment holes44,44for swage.

FIGS. 7A, 7B, 7C and 7Dare diagrams explaining the movable member5.FIG. 7Ais a plan view illustrating the movable member5as viewed from the upper side in the detent plate4-side.FIG. 7Bis a plan view illustrating the movable member5as viewed from the lower side in the pole board2-side.FIG. 7Cis a cross section illustrating the movable member5, taken along line A-A inFIG. 7B.FIG. 7Dis a plan view illustrating the magnet6as viewed from the lower side in the pole board2-side, explaining the magnet6embedded in the movable member5.

As illustrated inFIG. 7A, the movable member5has a plate-shaped base portion51formed in an arc shape as viewed in the rotation axis X direction. The base portion51has an inner edge portion511along a virtual circle Im1centered on the rotation axis X, and an outer edge portion512along a virtual circle Im2. The virtual circle Im1is formed in a diameter smaller than that of the virtual circle Ima (refer toFIG. 6). The virtual circle Im2is formed in a diameter larger than that of the virtual circle Imb (refer toFIG. 6).

Both sides of the inner edge portion511and the outer edge portion512in the circumferential direction around the rotation axis are respectively connected by a side edge portion513and a side edge portion514linearly extending in a radial direction of the rotation axis X.

Projections53,53to be inserted in the attachment holes43,43and projections54,54to be inserted in the attachment holes44,44are disposed on a top surface51aof the base portion51in the detent plate4-side.

The projections53,53,54,54project to the upper side in the detent plate4-side from the top surface51aof the base portion51.

As viewed in the rotation axis X direction, the projections53,53are disposed to be spaced from each other on the virtual circle Ima surrounding the rotation axis X at a predetermined interval.

As viewed in the rotation axis X direction, the projections54,54are disposed to be spaced from each other on the virtual circle Imb surrounding the rotation axis X at a predetermined interval.

As described above, the projections53,53,54,54in the movable member5-side are inserted in the attachment holes43,43,44,44in the detent plate4-side for swage (refer toFIG. 3A).

When the detent plate4turns around the rotation axis X in this state, the movable member5turns around the rotation axis X together with the detent plate4.

A recessed portion55formed in an arc shape as viewed in the rotation axis X direction is disposed in a region between the virtual circle Ima and the virtual circle Imb in the base portion51. The recessed portion55extends along the virtual circle Imc. The after-mentioned arc-shaped magnet6(refer toFIG. 7B, virtual line) is embedded in the recessed portion55.

The base portion51is provided with an abutting portion57disposed in the side edge portion513on one side in the circumferential direction around rotation axis X. The abutting portion57is disposed to project upward in the detent plate4-side from the base portion51.

As illustrated inFIG. 2B, the abutting portion57is disposed to make contact with a side edge40of the detent plate4at the time of fixing the movable member5to the detent plate4, thus suppressing the looseness of the movable member5.

As illustrated inFIG. 7B, an engaging portion56to be engaged to the groove24(refer toFIG. 4) in the pole board2-side is disposed on a bottom surface51bof the base portion51opposing the detent plate4.

As illustrated inFIG. 7C, in the base portion51the engaging portion56projects to the pole board2-side (the left side in the figure) from a position at the opposite side to the recessed portion55in the rotation axis X direction.

As illustrated inFIG. 7B, the engaging portion56, as viewed in the rotation axis X direction, is formed in an arc shape. The engaging portion56is formed from the one side edge portion513to the other side edge portion514in the base portion51along the virtual circle Imc surrounding the rotation axis X at a predetermined interval.

The engaging portion56is formed with an equal width W1over an entire length in the longitudinal direction. The width W1is set to a width wider than a width W3of the after-mentioned magnet6.

As viewed in the rotation axis X, the engaging portion56is formed in a shape matched to the groove24in the pole board2-side. As illustrated inFIG. 3A, when the detent plate4on which the movable member5is fixed is assembled via the hub3to the pole board2in the detecting device1, the engaging portion56of the movable portion5is accommodated in the groove24in the pole board2-side.

In the detecting device1, the movable portion5turns around the rotation axis X in association with the turning of the detent plate4around the rotation axis X.

Here, the width W1(refer toFIG. 7B) of the engaging portion56is set to the approximately same width as the width W1(refer toFIG. 4) of the groove24in the pole board2.

Further, a shape of the engaging portion56as viewed in the rotation axis X direction is formed in an arc shape matched to a shape of the groove24as viewed in the rotation axis X direction (refer toFIG. 4andFIG. 7B).

Therefore, when the movable portion5turns around the rotation axis X in association with the turning of the detent plate4around the rotation axis X, the engaging portion56of the movable member5can slidably move in the groove24of the pole board2in the longitudinal direction of the groove24.

In the movable member5, the magnet6is embedded in the inside of the engaging portion56. The magnet6is configured to be embedded in the inside of the movable member5at the time of resin-molding the movable member5.

In this state, the magnet6is arranged to project from the base portion51of the movable member5to the pole board2-side (refer toFIG. 3A).

As illustrated inFIG. 7B, in the movable member5one end6aof the magnet6in the longitudinal direction is positioned near the one side edge portion513of the base portion51, and the other end6bis positioned near the other side edge portion514.

Therefore, the one end6aand the other end6bof the magnet6are not exposed to the surface (the side edge portions513,514) of the movable member5.

As illustrated inFIG. 7C, a side surface6cof the magnet6in the pole board2-side and both of side surfaces6d,6din the width direction are positioned in the inside of the movable member5, and are not exposed to the surface of the movable member5. Therefore, the magnet6is completely embedded in the inside of the movable member5, and magnetic elements pulled in by a magnetic force of the magnet6do not directly adhere to the surface of the magnet6.

As illustrated inFIG. 7D, the magnet6is, as viewed in the rotation axis X direction, formed in an arc shape. As illustrated inFIG. 7B, the magnet6is embedded within a range shown in a virtual line along the virtual circle Imc surrounding the rotation axis X at a predetermined interval in the figure.

As illustrated inFIG. 7D, in the magnet6S poles and N poles alternately line in the longitudinal direction of the magnet6. In the present embodiment, one set of the S pole and the N pole positioned in the central part in the longitudinal direction are set in a range (in a sensor use range) used for detection of an angular position of the movable member5(the detent plate4) around the rotation axis X.

The S pole and the N pole positioned in both ends of the longitudinal direction are a magnet not used for detection of the angular position of the movable member5and are disposed to prevent the magnetic elements pulled in by the magnetic force of the magnet6from affecting the detection of the angular position of the movable member5.

As described above, the movable member5(detent plate4) turns around the rotation axis X at the time of switching the selection range in the automatic transmission. Therefore, the magnet6embedded in the movable member5moves in the circumferential direction around the rotation axis X at the time of switching the selection range in the automatic transmission.

As described above, the magnet6is disposed along the virtual circle Imc as viewed in the rotation axis X direction. Therefore, when the movable member5moves in the circumferential direction around the rotation axis X, the magnet6moves along the virtual circle Imc as viewed in the rotation axis X direction. That is, the virtual circle Imc shows a movement track of the magnet6.

FIGS. 8A and 8Bare diagrams explaining an operation of the detecting device1.FIG. 8Ais a diagram explaining a positional relation between the magnet6and the magnetic sensor75when the selection range in the automatic transmission is in a low position.FIG. 8Bis a diagram explaining the positional relation between the magnet6and the magnetic sensor75when the selection range in the automatic transmission is in a parking position.

FIG. 9is a graph illustrating a relation between an output signal of a magnetic sensitive element in the magnetic sensor75and the selection range in the automatic transmission.

The magnetic sensor75disposed in the pole board2is installed to meet the following condition in the detecting device1.

In a cross-sectional view along the rotation axis X, the magnetic sensor75is arranged to be opposed to the magnet6and to be spaced therefrom in the rotation axis X direction under the virtual circle Imc showing the movement track of the magnet6in the movable member5-side (refer toFIG. 3B).

As viewed in the rotation axis X direction, the magnetic sensor75is arranged in a position intersecting with the virtual circle Imc showing the movement track of the magnet6in the movable member5-side (refer toFIG. 8A).

(C) In any case when the selection range in the automatic transmission is in the low position (refer toFIG. 8A) and when the selection range in the automatic transmission is in the parking position (refer toFIG. 8B), the magnetic sensor75is arranged to be opposed to one of the S pole and the N pole positioned in the central part of the magnet6in the longitudinal direction.

The present embodiment adopts a single magnetic sensor that can detect both of a magnetic force of the N pole and a magnetic force of the S pole as the magnetic sensor75.

Specifically, the magnetic sensor75is provided with a single magnetic sensitive element detecting a change in a magnetic force of the N pole and a single magnetic sensitive element detecting a change in a magnetic force of the S pole.

The detecting device1outputs an output signal of the magnetic sensitive element detecting a change in a magnetic force of the N pole and an output signal of the magnetic sensitive element detecting a change in a magnetic force of the S pole via a wire connected to the connector portion27to an exterior.

For example, in a case where the selection range in the automatic transmission is in a parking “P” position, as illustrated inFIG. 8Bthe magnetic sensor75is arranged in a position to be opposed to the N pole of the magnet6.

In this state, as illustrated inFIG. 9an output value Lv_N of the magnetic sensitive element detecting the magnetic force of the N pole is larger than an output value Lv_S of the magnetic sensitive element detecting the magnetic force of the S pole.

An external device that receives an output signal of the detecting device1is set to determine that the selection range in the automatic transmission is in the parking “P” position when the output value of the magnetic sensitive element detecting the magnetic force of the N pole becomes the maximum value and when the output value of the magnetic sensitive element detecting the magnetic force of the S pole becomes the minimum value.

Hereinafter, determination criteria of the selection range in the automatic transmission will be listed.

When the output value of the magnetic sensitive element detecting the magnetic force of the N pole and the output value of the magnetic sensitive element detecting the magnetic force of the S pole each are not any one of the maximum value and the minimum value and when the output value of the magnetic sensitive element detecting the magnetic force of the N pole is larger than the output value of the magnetic sensitive element detecting the magnetic force of the S pole, the selection range in the automatic transmission is determined to be in a reverse (backward travel range) “R” position.

When the output value of the magnetic sensitive element detecting the magnetic force of the N pole and the output value of the magnetic sensitive element detecting the magnetic force of the S pole each are an approximately intermediate value between the maximum value and the minimum value and when the output value of the magnetic sensitive element detecting the magnetic force of the N pole is approximately equal to the output value of the magnetic sensitive element detecting the magnetic force of the S pole, the selection range in the automatic transmission is determined to be in a neutral “N” position.

When the output value of the magnetic sensitive element detecting the magnetic force of the N pole and the output value of the magnetic sensitive element detecting the magnetic force of the S pole each are not any one of the maximum value and the minimum value and when the output value of the magnetic sensitive element detecting the magnetic force of the N pole is smaller than the output value of the magnetic sensitive element detecting the magnetic force of the S pole, the selection range in the automatic transmission is determined to be in a drive (forward travel range) “D” position.

The selection range in the automatic transmission is determined to be in a low “L” position when the output value of the magnetic sensitive element detecting the magnetic force of the N pole becomes the minimum value and when the output value of the magnetic sensitive element detecting the magnetic force of the S pole becomes the maximum value.

It should be noted that a determination of the selection range by comparison between the output value of the magnetic sensitive element of the N pole and a threshold value and a determination of the selection range by comparison between the output value of the magnetic sensitive element of the S pole and a threshold value may be combined.

In this case, in a case where the selection range determined by the output value of the magnetic sensitive element of the N pole corresponds to the selection range determined by the output value of the magnetic sensitive element of the S pole, the corresponding selection range is determined to be the selection range in the automatic transmission. It should be noted that in a case of non-correspondence, for example, the magnetic sensor75is determined to be abnormal, and the abnormality of the magnetic sensor75can be notified.

Here, in a case where the magnetic sensor75is provided with the single magnetic sensitive element only that detects the magnetic force of the N pole or the S pole, an output signal of any one of a solid line (a characteristic line showing an output change in the magnetic sensitive element of the N pole) and a dashed-dotted line (a characteristic line showing an output change in the magnetic sensitive element of the S pole) inFIG. 9is outputted from the detecting device1.

In this case, the selection range in the automatic transmission is determined by the comparison between the output value of the magnetic sensitive element and the threshold value.

The magnetic sensor75provided with the magnetic sensitive element detecting the magnetic force of the N pole and the magnetic sensitive element detecting the magnetic force of the S pole each has two determination criteria for determining the selection range. Therefore, the determination accuracy improves more than in a case where the magnetic sensor75is provided with the single magnetic sensitive element only detecting the magnetic force of the N pole or the S pole.

Further, even in a case where one of the magnetic sensitive element detecting the magnetic force of the N pole and the magnetic sensitive element detecting the magnetic force of the S pole is damaged, it is possible to secure the function as the magnetic sensor75. That is, it is possible to ensure redundancy of the detecting device1.

An explanation will be made of the operation of the detecting device1.

When the selection range in the automatic transmission is changed from “the parking position” to “the low position”, the unillustrated manual shaft rotates to cause the hub3and the detent plate4to turn around the rotation axis X.

Thereby, the movable member5fixed to the detent plate4and the magnet6embedded in the inside of the movable member5move in the circumferential direction around the rotation axis X.

Then, the positional relation between the magnetic sensor75and the N pole and the S pole of the magnet6changes caused by the movement of the magnet6(refer toFIGS. 8A and 8B).

As described above, since the magnetic sensor75is provided with one magnetic sensitive element detecting the magnetic force of the N pole and one magnetic sensitive element detecting the magnetic force of the S pole, the magnetic sensor75outputs an output signal showing the detected magnetic force of the N pole and an output signal showing the detected magnetic force of the S pole.

Thereby, the external equipment device that has received the output signals determines the angular position of the detent plate4around the rotation axis X from each of the output signal showing the detected magnetic force of the N pole and the output signal showing the detected magnetic force of the S pole to determine the selection range in the automatic transmission.

Specifically, when the selection range is changed from “the parking position” to “the low position”, the positional relation between the magnetic sensor75and the magnet6changes from the positional relation illustrated inFIG. 8Bto the positional relation illustrated inFIG. 8A.

Thereby, the output signal of the magnetic sensor75changes from a state (A) to a state (B) as followed.

The state (A): the output value of the magnetic sensitive element detecting the magnetic force of the N pole is the maximum value and the output value of the magnetic sensitive element detecting the magnetic force of the S pole is the minimum value.

The state (B): the output value of the magnetic sensitive element detecting the magnetic force of the N pole is the minimum value and the output value of the magnetic sensitive element detecting the magnetic force of the S pole is the maximum value.

In this way, the output value of the magnetic sensitive element detecting the magnetic force of the N pole and the output value of the magnetic sensitive element detecting the magnetic force of the S pole change in response to the switching of the selection range in the automatic transmission. As a result, the selection range in the automatic transmission can be determined in the external equipment device into which the output signal of the detecting device1(the magnetic sensor75) is inputted.

Here, at the switching of the selection range in the automatic transmission, the engaging portion56of the movable member5moves within the groove24of the pole board2in the longitudinal direction (in the circumferential direction around the rotation axis X) of the groove24.

As described above, the magnet6is covered with a resin material configuring the movable member5, and is thereby configured in such a manner as to prevent magnetic elements from directly adhering to the magnet6even in a case where metallic powder (magnetic elements) in the automatic transmission is pulled in by the magnetic force.

Further, since the engaging portion56has both side surfaces56dalong the movement direction in the groove24and a bottom surface56cin the pole board2-side that are covered with the resin material configuring the pole board2, the magnetic elements do not adhere to both the side surfaces56dand the bottom surface56cas well (refer toFIG. 3A).

On the other hand, since one end56aand the other end56bof the engaging portion56in the longitudinal direction are exposed to the inside of the groove24, the magnetic elements possibly adhere.

In the present embodiment, one set of the S pole and the N pole positioned in the central part of the magnet6in the longitudinal direction is a magnet used for the detection of the selection range by the magnetic sensor75, and the S pole and the N pole positioned in both ends of the magnet6in the longitudinal direction are a magnet not used for the detection of the selection range by the magnetic sensor75.

Therefore, even if the magnetic elements pulled in by the magnetic force of the magnet6adhere to the one end56aand the other end56bof the engaging portion56in the longitudinal direction, an effect of the magnetic elements having adhered thereto is caused to stay in the magnet (the N pole and the S pole) in both the ends not used for the detection by the magnetic sensor75.

Therefore, even if the magnetic elements pulled in by the magnetic force of the magnet6adhere to the one end56aand the other end56bof the engaging portion56in the longitudinal direction, the effect of the magnetic elements having adhered thereto is configured in such a manner as not to reach the magnetic force of the magnet (the N pole and the S pole) in the central part used for the detection by the magnetic sensor75.

As a result, the angular position of the detent plate4around the ration axis X can be accurately determined to determine the selection range in the automatic transmission.

In addition, in the present embodiment a length of the engaging portion56in the circumferential direction around the ration axis X is set such that when the selection range in the automatic transmission becomes “in the parking position”, the one end56aof the engaging portion56projects outside from the groove24, and when the selection range in the automatic transmission becomes “in the low position”, the other end56bof the engaging portion56projects outside from the groove24(refer toFIG. 2A,FIG. 8AandFIG. 8B).

Therefore, even if the magnetic elements pulled in by the magnetic force of the magnet stagnate in the inside of the groove24, when the engaging portion56moves in the circumferential direction around the rotation axis X at the switching of the selection range, the magnetic elements stagnant in the inside of the groove24are pushed by the one end56aor the other end56bof the engaging portion56to be discharged outside of the groove24.

As a result, the event that the magnetic elements stagnant in the inside of the groove24get together to interrupt the movement of the movable member5(the engaging portion56) is prevented from being caused.

As described above, the detecting device1according to the present embodiment has the configuration as follows.

The detecting device1includes the movable member5, the pole board2(the fixing member), the single magnet6, and the single magnetic sensor75.

The movable member5moves in the circumferential direction around the rotation axis X in association with the switching in the selection range in the automatic transmission.

The pole board2supports the hub3rotating together with the movable member5to be rotatable around the rotation axis X.

The magnet6is disposed in the movable member5, and the N pole and the S pole line in the movement direction of the movable member5(in the circumferential direction around the rotation axis X).

The magnetic sensor75is disposed on the printed board7installed on the pole board2.

As viewed in the direction (the rotation axis X direction) perpendicular to the movement direction of the movable member5, the magnetic sensor75is arranged to be opposed to the magnet6on the movement track (the virtual circle Imc) of the magnet6.

With this configuration, when the positional relation between the magnetic sensor75and the magnet6changes caused by the movement of the movable member5, the magnetic force that is detected by the magnetic sensor75changes. Thereby, the selection range in the automatic transmission can be determined based upon a magnitude of the magnetic force detected by the magnetic sensor75.

Since the selection range in the automatic transmission can be detected by a combination of the single magnet6and the single magnetic sensor75, it is possible to provide the detecting device1less expensively.

The detecting device1according to the present embodiment has the configuration as follows.

The magnet is disposed to project to the pole board2-side from the movable member5.

The groove24capable of accommodating the magnet6is disposed in the opposing portion of the pole board2to the movable member5.

As viewed in the rotation axis X direction, the groove24is disposed along the movement track (the virtual circle Imc) of the magnet6, and the one end24aand the other end24bof the groove24in the longitudinal direction open to the side surface21cand the side surface21dof the pole board2.

In the magnet6, the magnet (the N pole and the S pole) not used for the detection by the magnetic sensor75are connected to the one end6aand the other end6bin the longitudinal direction along the movement direction.

The magnetic elements pulled in by the magnetic force of the magnet6possibly advance into the groove24.

The groove24in which the magnet6moves in association with the movement of the movable member5is configured such that the one end24aand the other end24bof the groove24in the longitudinal direction open to the side surfaces21c,21dof the pole board2.

In a case where the magnet (a dummy magnet) not used for the detection by the magnetic sensor75is not disposed, when the magnetic element having advanced into the groove24adheres to the magnet6, the detection of the magnetic force by the magnetic sensor75is affected. As a result, there is a possibility that the selection range in the automatic transmission cannot be appropriately detected.

Since the dummy magnet is not used for the detection of the magnetic sensor75, even if the magnetic element adheres to a portion of the dummy magnet, the detection by the magnetic sensor75is not affected. Thereby, it is possible to appropriately detect the selection range in the automatic transmission.

The detecting device1according to the present embodiment has the configuration as follows.

The magnet6is embedded in the resin material as a constituent material of the movable member5.

The magnet6is embedded in the engaging portion56formed integrally with the movable member5.

With this configuration, the surface of the magnet6is protected with the constituent material (resin material: non-magnetic element) of the movable member5. The magnet6slides and moves in the longitudinal direction in the inside of the groove24. Since the surface of the magnet6is protected by the engaging portion56of the movable member5, it is possible to prevent the abrasion of the magnet6.

In addition, the magnetic element having advanced into the groove24can be prevented from making direct contact with the surface of the magnet6.

In addition, even in a case where the magnetic element in the groove24adheres to the surface of the engaging portion56of the movable member5, since a retaining force of the magnetic element is weaker than in a case where the magnetic element directly adheres to the magnet6, it is possible to remove the magnetic element having adhered to the surface of the movable member5at a time point when the magnet6reaches the opening of the one end24aor the other end24B of the groove24.

The detecting device1according to the present embodiment has the configuration as follows.

The magnetic sensor75comprises a single magnetic sensor that can detect the magnetic force of the N pole and the magnetic force of the S pole simultaneously.

When the positional relation between the magnetic sensor75and the magnet6changes caused by the movement of the movable member5, the magnetic force of the N pole and the magnetic force of the S pole that are detected by the magnetic sensor75change. When a magnetic sensor that can detect both of the magnetic force of the N pole and the magnetic force of the S pole to be detected is adopted, it is possible to determine the selection range in the automatic transmission by using both of the detected magnetic force of the N pole and the detected magnetic force of the S pole. Therefore, the detection accuracy improves.

The detecting device1according to the present embodiment has the configuration as follows.

The movable member5is supported through the detent plate4and the hub3to be rotatable around the rotation axis X by the pole board2.

As viewed in the rotation axis X direction, the magnet6and the groove24are formed in an arc shape surrounding the rotation axis X at a predetermined interval.

With this configuration, it is possible to provide the detecting device1inexpensively that is difficult to be subjected to the influence of the metallic powder (the magnetic element) in the transmission case.

In addition, since the detecting device1configured such that the movable member5turns around the rotation axis X can be miniaturized, a degree of freedom in the installation in the transmission case improves.

In the embodiment, the detected device1configured such that the movable member5and the magnet6turn around the rotation axis X is shown as an example, but a detected device configured such that the movable member5and the magnet6move forward/backward in an axial direction may be adopted.

In this case, a magnet in which N poles and S poles alternately line is formed in a straight line shape, and a magnet not used for detection by the magnetic sensor75is connected to both ends of the magnet in the longitudinal direction and the magnet is embedded in a constituent material of a movable member. As a result, the same effect as that of the above-mentioned embodiment can be obtained.

It should be noted that in the embodiment, a case where the detecting device1detects the selection range in the automatic transmission is shown as an example. The present invention is not limited to the aspect of the embodiment.

For example, the present invention can be, in an equipment device in which one of a plurality of selections is selected by an operation of a detection object, used for determination of the selected selection.

For example, the present invention can be suitably applied to a switch device switching a selection in accordance with an angular position of a dial type knob around a rotation axis, a switch device switching a selection in accordance with a position of a knob linearly moving, and the like.

While only the selected embodiment and the modification examples have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims. Furthermore, the foregoing description of the embodiment and the modification examples according to the present invention is provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.