JP2012208013A - Rotation type sensor and detection device comprising rotation type sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotation type sensor and a detection device, capable of assembling by accurately aligning a rotor center of the rotation type sensor and a shaft core of a rotation shaft when the rotation type sensor is installed to an installation base material member on which the rotation shaft is supported.SOLUTION: In a rotation type sensor 1, a positioning recess 4 and a rotation supporting hole 3 are integrally formed on a base 2 by a same metal mold, and a rotor 7 is freely rotatably supported by the rotation supporting hole 3. In an installation base material 21 to be installed with the rotation type sensor 1, a reference protrusion 22 and a holding recess 25 are integrally formed by the same metal mold, and a rotation shaft 28 is freely rotatably supported by a bearing member 26 held by the holding recess 25. Consequently, a shaft core of the rotation shaft 28 and a center of a shaft connecting hole 8 of the rotor 7 can be made to coincide by fitting the positioning recess 4 to the reference protrusion 22.

Description

  The present invention relates to a rotation sensor having a base, a rotor, and a detection unit, and a detection device including the rotation sensor, and in particular, by simply installing the base on a mounting base material, the rotation center of the rotor can be determined. The present invention relates to a rotary sensor and a detection device that can be positioned.

  In rotating electronic components provided in various electronic devices, a rotating body is rotatably supported on a substrate. A resistor and a current collector are formed in an annular shape on the substrate, and a slider for sliding the resistor and the current collector is provided on the rotating body. The operating shaft is press-fitted into the insertion hole formed in the rotating body, and the rotating body is rotated by the operating shaft, whereby a variable output in which the resistance value changes is obtained.

  The rotary electronic component described in Patent Document 1 is formed with an insertion hole through which the operation shaft is inserted into the substrate, and is raised concentrically with the insertion hole on the back surface of the substrate in a ring shape. A protrusion is formed. The rotary electronic component is attached to a printed circuit board. The protruding portion is fitted into a hole formed in the printed circuit board, and the terminal protruding from the printed circuit board is soldered to the surface of the printed circuit board with the rotation center of the rotating body positioned on the printed circuit board.

JP 2003-7516 A

  In the rotary electronic component described in Patent Document 1, the rotation center of the rotating body is positioned with respect to the printed board. For this reason, if the printed circuit board to which the rotating electronic component is attached is further attached to a mounting base material such as a housing, the mounting tolerance between the printed circuit board and the mounting base material is the rotation center of the mounting base material and the rotating body. Therefore, it is difficult to maintain high positional accuracy of the rotating body with respect to the mounting base material.

  For example, on the basis of the structure described in Patent Document 1, if an attempt is made to configure a detection device in which the operating shaft is rotatably supported by a bearing provided on the mounting base material, the central axis of the operating shaft and the rotating body Even if the operation shaft cannot be press-fitted into the rotating body due to excessively large positional deviation tolerance with the center of rotation, the positional deviation tolerance becomes large and the rotational load of the rotating body becomes extremely large. The problem that the operability deteriorates is likely to occur.

  The present invention solves the above-described conventional problems, and a rotary sensor and a rotary type that can accurately position the rotation center of a rotor supported by a base with respect to a mounting base material such as a housing. It aims at providing the detection apparatus provided with the sensor.

  In the present invention, even if the rotating shaft is rotatably supported by a bearing portion provided on a mounting base material such as a housing, the rotor rotates when the base is attached to the mounting base material. A rotary sensor and a rotary sensor that can reduce a misalignment error between the center and the axis of the rotary shaft, can reliably connect the rotary shaft and the rotor, and can prevent an increase in rotational load of the rotary shaft, etc. An object of the present invention is to provide a detection device provided.

The present invention provides a rotary sensor having a base, a rotor rotatably supported by the base, and a detection unit that detects the rotation of the rotor.
The base is formed of a synthetic resin, and a positioning recess that fits into the base is provided with a rotation support hole that rotatably supports the rotor and a reference convex provided on a mounting base on which the base is installed. And the inner peripheral surface of the positioning recess has a cylindrical surface having a diameter larger than the inner diameter of the rotation support hole, and the cylindrical surface and the inner peripheral surface of the rotation support hole Are formed in concentric circles.

  In the present invention, the rotation support hole and the positioning concave portion are molded by the same convex portion provided in the mold.

  The rotation type sensor of the present invention is such that the positioning recess formed on the base is fitted to the reference convex portion provided on the mounting base material such as the housing, thereby rotating the rotor with respect to the mounting base material. It is possible to accurately position the center.

  For example, the rotating shaft is rotatably supported by a bearing hole formed in the mounting base material, or the rotating shaft is rotatably supported by a bearing member such as a bearing held by the mounting base material. Even with a structure that is supported rotatably with respect to the bearing on the material side, when the rotary sensor is mounted on the mounting base material, the rotor center of rotation and the axis of the rotating shaft are accurately positioned. it can. Therefore, the rotating shaft supported on the mounting base material side and the rotor rotatably supported by the base can be easily connected, and the rotating load of the rotor is abnormal when the rotating shaft is rotated. It is possible to avoid such an increase.

  In the present invention, it is preferable that the base is formed with a rotation stopper recess that extends in a radial direction from the center of the positioning recess continuously with the cylindrical surface.

  When the base is attached to the mounting base by fitting not only the positioning recess provided on the base but also the non-rotating recess into a reference convex formed on the base, the base is rotated. Can be positioned. Therefore, the rotation angle and rotation phase of the rotor can be determined with reference to the mounting base material.

In the present invention, the detection unit includes a resistor layer provided on the base and a conductive slider provided on the rotor and sliding on the surface of the resistor layer. ,
The resistor layer is provided on a surface of the base opposite to the surface on which the positioning recess is provided, and the resistor layer is an arc portion along an arc locus centering on a rotation center line of the rotor. It is preferable that the arc portion is formed at a position that does not overlap the positioning recess.

Further, in the invention, the detection unit includes a resistor layer provided on the base, and a conductive slider provided on the rotor and sliding on the surface of the resistor layer. And
The resistor layer is provided on a surface of the base opposite to the surface on which the positioning recess is provided, and the resistor layer is an arc portion along an arc locus centering on a rotation center line of the rotor. And a discontinuous part in which a part of the arc part is interrupted,
It is preferable that the arc portion is formed at a position that does not overlap the positioning recess, and the discontinuous portion is formed at a position that overlaps the rotation stopper recess.

As described above, in the base, by forming the resistor layer at a position that does not overlap with the positioning recess or the like, the resistor layer can be disposed in a portion where the thickness of the base is large. A portion having a large thickness on the base has high strength, is less likely to be deformed due to a temperature change, and easily maintains the flatness of the surface during manufacturing. Therefore, when the resistor layer is provided in this portion, the resistor layer can be reliably held for a long period of time, and it is easy to suppress a decrease in rotation detection accuracy due to environmental changes.
In the present invention, the base is provided with a terminal portion that is electrically connected to the detection portion.

Furthermore, the present invention provides a detection apparatus including any one of the rotation type sensors and a mounting base material to which the rotation type sensor is attached.
The mounting base material is formed of a synthetic resin, and the mounting base material is provided with a reference convex portion and a bearing portion that supports a rotating shaft that passes through the center of the reference convex portion, and an outer peripheral surface of the reference convex portion And the inner peripheral surface of the bearing portion are formed concentrically,
The rotating shaft is connected to the rotor in a state in which the positioning recess is fitted to the reference protrusion.

  In the present invention, it is preferable that the inner peripheral surface of the bearing portion is formed by the convex portion of one mold, and the outer peripheral surface of the reference convex portion is molded by the concave portion of the other mold.

  In the present invention, a printed wiring board is provided between the mounting base material and the base, and a relief hole through which the reference convex portion is inserted through a gap is formed in the printed wiring board. The terminal part provided in the said base can be soldered to the land part of the said printed wiring board, and it can comprise as the said printed wiring board being fixed to the said mounting base material.

  In this case, a mounting hole is opened in the printed wiring board, a mounting screw is inserted into the mounting hole with a gap, and the mounting screw is formed in a hole (for example, a female screw hole) formed in the mounting base material. And the printed wiring board is fixed to the mounting base material.

  The detection device according to the present invention is configured such that when the printed wiring board is installed on the mounting base material after the terminal portion of the rotational sensor is soldered to the land portion of the printed wiring board, the rotational sensor base and the mounting base material are mounted. The mounting tolerance between the printed wiring board and the mounting base material is not added to the positional deviation of the rotation center of the rotating body.

  According to the present invention, when the base of the rotary sensor is attached to an attachment base material such as a housing, the positioning concave portion of the base can be fitted to the reference convex portion of the attachment base material, and as a result, the rotor It is possible to position the center of rotation with high accuracy with reference to the mounting base material.

  Therefore, even if the rotating shaft is rotatably supported by the bearing portion provided on the mounting base material side, by fixing the base to the mounting base material, the rotation center of the rotor and the rotating shaft It becomes possible to accurately position and connect the shaft core.

1 is an exploded perspective view showing a rotary sensor according to an embodiment of the present invention and a detection device to which the rotary sensor is attached; The perspective view which shows a rotation type sensor and a rotating shaft, Exploded perspective view showing the base of the rotary sensor and the rotor and slider; Front view of the base viewed from the rotor side, A longitudinal sectional view showing the upper body in which the rotary sensor is mounted on the mounting base material, FIG. 4 is a cross-sectional view of the base shown in FIG.

  The structure of the rotary sensor 1 according to the embodiment of the present invention will be described with reference to FIGS.

  The rotary sensor 1 has a base 2. The base 2 is made of synthetic resin and is molded by an injection molding method using a mold. As shown in FIG. 3, the side of the base 2 facing the rotor 7 is the operation side surface 2 a, and as shown in FIG. 2, the side installed on the attachment base material 21 is the installation side surface 2 b. As shown in FIG. 6, the operation side surface 2a and the installation side surface 2b are planes parallel to each other. Moreover, the shape of the front seen from the operation | movement side surface 2a and the shape of the back seen from the installation side surface 2b are substantially square shapes.

  As shown in FIGS. 3, 4, and 6, the rotation support hole 3 is formed through the base 2 so as to penetrate therethrough. The rotation support hole 3 opens in the operation side surface 2a. An inner peripheral surface 3 a of the rotation support hole 3 is a cylindrical surface having a center of curvature at a rotation center line O <b> 1 indicating the rotation center of the rotor 7.

  As shown in FIGS. 2 and 6, a positioning recess 4 is provided on the installation side surface 2b of the base 2, and the positioning recess 4 is open to the installation side surface 2b. Most of the inner peripheral surface of the positioning recess 4 is a cylindrical surface 4a. The cylindrical surface 4a has a center of curvature at the rotation center line O1 and is formed with a constant radius. On the installation side surface 2 b, a rotation stopper recess 5 that is continuous with the positioning recess 4 is formed. As shown in FIG. 2, the rotation preventing recess 5 extends further outward in the radial direction (radial direction) around the rotation center line O1 from the cylindrical surface 4a. The inner wall surface 5a of the rotation stopper recess 5 is formed with a certain width in the left-right direction and is continuous with the cylindrical surface 4a.

  As shown in FIG. 6, the rotation support hole 3 and the positioning recess 4 are formed continuously, and the inner peripheral surface 3a and the cylindrical surface 4a of the rotation support hole 3 are continuous via the step surface 4c. . The step surface 4c is a plane parallel to both the operation side surface 2a and the installation side surface 2b.

  When the base 2 is injection-molded, the rotation support hole 3 and the positioning recess 4 are simultaneously formed with the same mold. That is, a convex part is provided in the mold that forms the installation side surface 2b, and the rotational support hole 3 and the positioning concave part 4 are simultaneously molded by this convex part. Therefore, as shown in FIG. 6, the inner peripheral surface 3a (inner diameter dimension D1) of the rotation support hole 3 and the cylindrical surface 4a (inner diameter dimension D2) of the positioning recess 4 are positioned concentrically around the rotation center line O1. Therefore, the positional deviation tolerance at the center of each of the inner diameter dimensions D1 and D2 is extremely small.

  As shown in FIG. 6, the positioning recess 4 is formed by digging to a predetermined depth from the installation side surface 2b, and the thickness dimension T2 between the operation side surface 2a and the step surface 4c is It is less than half of the maximum value T1 of the thickness dimension of 2.

  As shown in FIG. 2, the installation surface 2b of the base 2 is provided with positioning pins 6a and 6b that integrally project rearward from both the upper side of the positioning recess 4 and the lower side of the rotation stopper recess 5. It has been.

  As shown in FIGS. 3 and 4, a resistor layer 11 is formed on the operation side surface 2 a of the base 2. The resistor layer 11 is formed mainly of carbon having a relatively high specific resistance. The resistor layer 11 is formed in a ring-shaped pattern having a constant radius centered on the rotation center line O1 between one end portion 11a and the other end portion 11b. The portion of the width dimension W1 between the end portion 11a and the end portion 11b is a discontinuous portion 12 of the resistor layer 11, and the discontinuous portion 12 is a detection region for detecting the rotation of the rotor 7. Absent.

  An electrode layer 13a continuous with one end 11a of the resistor layer 11 and an electrode layer 13b continuous with the other end 11b are formed below the operating surface 2a. The electrode layer 13a and the electrode layer 13b are made of a low-resistance material mainly composed of silver, but the surface appearing on the operation side surface 2a is covered with a layer mainly composed of carbon continuous with the resistor layer 11. ing.

  As shown in FIGS. 3 and 4, a common electrode layer 14 that is a current collector pattern is provided on the center side of the resistor layer 11. The common electrode layer 14 is formed in a ring-shaped pattern that is continuous with a constant radius centered on the rotation center line O1. The common electrode layer 14 is made of a low resistance material mainly composed of silver, and the surface appearing on the operation side surface 2 a is covered with a layer of a high resistance material mainly composed of carbon similar to the resistor layer 11.

  As shown in FIG. 6, the resistor layer 11, the electrode layers 13 a and 13 b, and the common electrode layer 14 are embedded in the base 2, and each surface is substantially the same as the operation side surface 2 a of the base 2. It is the same plane.

  The resistor layer 11, the electrode layers 13a and 13b, and the common electrode layer 14 can be formed integrally with the base 2 by a so-called imprint method.

  The imprint method in the present embodiment uses a transfer plate formed of a thin metal plate such as a brass plate. A carbon paste in which carbon black or carbon fiber is mixed in a binder resin is used, and this carbon paste is applied to the surface of the transfer plate by a printing method and cured to form the resistor layer 11 and the electrode layers 13a and 13b continuous therewith. A carbon layer having the pattern shape is formed. At the same time, a carbon layer having a pattern shape of the common electrode layer 14 is formed. Next, a silver paste in which silver powder is mixed with a binder resin is used, and a layer of silver paste is applied over the carbon layer by a printing method in the electrode layers 13a and 13b. At the same time, a silver paste is applied over the carbon layer over the entire common electrode layer 14 by a printing method.

  After the silver paste is cured, the transfer plate is placed in the mold, and a synthetic resin material is injected into the mold to mold the base 2. At this time, the resistor layer 11, the electrode layers 13a and 13b, and the common electrode layer 14 on the surface of the transfer plate are embedded in the base 2, and the operation side surface 2a is molded on the surface of the transfer plate. After the synthetic resin is solidified in the shape of the base 2, the transfer layer is peeled off, so that the resistor layer 11, the electrode layers 13a and 13b, and the common electrode layer 14 are integrated with the base 2 as shown in FIG. It is formed.

  As shown in FIG. 6, the radius from the rotation center line O1 of the inner peripheral edge of the resistor layer 11 is larger than the radius (D2 / 2) of the cylindrical surface 4a of the positioning recess 4, and the resistor layer 11 is positioned in the positioning recess 4 It is formed in a region that does not overlap. Further, as shown in FIG. 4, the rotation preventing recess 5 is located at the discontinuous portion 12 (the portion of the width dimension W1) of the resistor layer 11, and the end portions 11 a and 11 b of the resistor layer 11 are prevented from being rotated. The resistor layer 11 is formed in a region that does not overlap with the rotation stopper recess 5. That is, the resistor layer 11 is formed in the region where the thickness dimension of the base 20 is T1, and the resistor layer 11 is not formed in the region where the thickness dimension T2 is thin.

  As shown in FIG. 6, the thickness dimension of the part in which the positioning recessed part 4 and the rotation prevention recessed part 5 are formed is thin, and the thickness dimension of the base 2 is T2 which is half or less of the maximum value T1. Further, the thin portion is close to the inner peripheral surface 3 a of the rotation support hole 3.

  The resistor layer 11 is formed in the region having the thickness dimension T1 without overlapping the region having the thickness dimension T2. Since the thick region has high strength and is difficult to deform even in a high temperature environment, the resistor layer 11 is held on the substrate 2 for a long period of time while maintaining the flatness when the resistor layer 11 is transferred at the time of manufacture. be able to. Therefore, it is possible to suppress the contact load, the contact resistance, and the like when the slider 17 slides on the surface of the resistor layer 11 from being affected by the environmental temperature, and the voltage change corresponding to the rotation angle is highly accurate. Can be detected.

  As shown in FIGS. 3 and 4, when the base 2 is injection-molded, the lead terminals 15 a and 15 b and the common lead terminal 16 are embedded in the base 2. The lead terminals 15a and 15b and the common lead terminal 16 are formed of a metal plate. The electrode layer 13a is formed in contact with the surface of the lead terminal 15a, and the electrode layer 13b is formed in contact with the surface of the lead terminal 15b. As shown in FIG. 4, the lead terminals 15 a and 15 b protrude downward from the lower portion of the base 2. The common electrode layer 14 is formed in contact with the surface of a contact portion 16 a formed at the central portion of the common lead terminal 16, and the terminal portions 16 b and 16 c protrude upward from the upper portion of the base 2.

  As shown in FIGS. 3 and 5, in the rotary sensor 1, a rotor 7 is rotatably attached to a base 2. The rotor 7 is made of a synthetic resin material.

  As shown in FIGS. 3 and 5, the rotor 7 is formed on the back side where the rotating shaft portion 7 a whose outer peripheral surface is a cylindrical surface faces the base 2, and the rotating shaft portion 7 a is the rotation of the base 2. The rotor 7 is rotatably supported with respect to the base 2 through the support hole 3 without a gap. The rotor 7 is integrally formed with a support flange portion 7b in front of the rotating shaft portion 7a, and the slider 17 is formed on the support flange portion 7b with a conductive and spring metal plate. Is fixed.

  As shown in FIG. 3, the slider 17 has a center hole 17a into which the rotation shaft portion 7a of the rotor 7 is inserted at the center. A fixing portion 17b is formed on the outer periphery of the center hole 17a. When the rotor 7 is injection-molded with a synthetic resin material, the fixing portion 17b is embedded in the rotor 7 and fixed integrally therewith. Alternatively, the slider 17 may be fixed to the rotor 7 by a caulking structure.

  As shown in FIG. 5, a cover member 19 is attached in front of the base 2. The cover member 19 is made of synthetic resin. After the rotating shaft portion 7a of the rotor 7 to which the slider 17 is fixed is rotatably inserted into the rotation support hole 3 of the base 2, the cover member 19 is fitted and fixed to the base 2. . At this time, the shaft-like protruding portion 7 c protruding forward from the support flange portion 7 b in the rotor 7 is inserted into the hole 19 a formed in the cover member 19. Further, the cover member 19 is formed with a pressing ring portion 19b that protrudes from the periphery of the hole 19a toward the base 2, and the supporting flange portion 7b of the rotor 7 is attached to the base 2 by the pressing ring portion 19b. It is pressed toward.

  As a result, the elastically deformable detection sliding portion 17c formed on the slider 17 is elastically pressed (pressed and contacted) on the surface of the resistor layer 11, and is also elastically deformable formed on the slider 17. The common sliding portion 17d is pressed against the surface of the common electrode layer 14 (pressed and contacted).

  The resistor 10, the common electrode layer 14, and the slider 17 constitute the detection unit 10. In the detection unit 10, when the rotor 7 rotates together with the slider 17 in a state where a constant voltage is applied between the extraction terminal 15 a and the extraction terminal 15 b, the detection sliding unit on the resistor layer 11 is detected. The voltage extracted from the common electrode layer 14 and the common lead terminal 16 (terminal portions 16b and 16c) changes according to the change in the contact position of 17c. The rotation angle of the rotor 7 is detected by this voltage change.

  As shown in FIG. 6, the resistor layer 11 is formed in a thick portion of the base 2 with a thickness dimension T1, and the flatness of the surface is maintained. The contact state with the body layer 11 is stabilized over the entire rotation range of the rotor 7. For this reason, the rotation angle of the rotor 7 can be accurately detected over a long period of time, such as a change in contact load (contact pressure) between the detection sliding portion 17c and the resistor layer 11 is reduced and a change in contact resistance is reduced. Become.

  As described above, the rotor 7 and the slider 17 are attached to the base 2, and the cover member 19 covering the operation side surface 2 a is attached, and the assembly of the rotary sensor 1 is completed.

  As shown in FIGS. 1 and 2, the rotary shaft is not attached to the rotor 7 when the assembly of the rotary sensor 1 is completed. The rotation shaft portion 7 a of the rotor 7 is exposed from the rotation support hole 3 of the base 2 toward the installation side surface 2 b, and the shaft-like protruding portion 7 c of the rotor 7 extends from the hole 19 a formed in the cover member 19. It is exposed forward. The rotor 7 is formed with a shaft coupling hole 8 penetrating in the front-rear direction, and this shaft coupling hole 8 is also exposed on both the back and the front of the rotary sensor 1. The shaft coupling hole 8 is a substantially D-shaped non-circular through hole having a round hole portion 8a and a flat surface portion 8b.

  As shown in FIGS. 1 and 5, the rotary sensor 1 is attached to an attachment base material 21, and the shaft connecting hole 8 and the rotary shaft 28 are connected to form a detection device 20.

  The mounting base material 21 on which the rotary sensor 1 is installed is a part of the casing of the electronic device or is fixed inside the casing.

  The attachment base material 21 is integrally formed of a synthetic resin material, and has a support side surface 21a to which the rotary sensor 1 is attached and an operation side surface 21b opposite to the support side surface 21a. The support side surface 21a and the operation side surface 21b are planes parallel to each other.

  As shown in FIGS. 1 and 5, a reference protrusion 22 is integrally formed on the support-side surface 21 a of the mounting base 21 so as to protrude. A reference cylindrical surface 22 a is formed on the outer periphery of the reference convex portion 22. The reference cylindrical surface 22 a is formed with a constant radius centered on the support center line O <b> 2 set on the mounting base material 21. The outer diameter dimension Da of the reference cylindrical surface 22a shown in FIG. 1 is a cylindrical surface that is a part of the inner peripheral surface of the positioning recess 4 formed in the base 2 of the rotary sensor 1 shown in FIG. The reference cylindrical surface 22a of the reference convex portion 22 can be fitted into the cylindrical surface 4a of the positioning concave portion 4 with a minimum gap.

  As shown in FIG. 1, a detent reference convex portion 23 is formed integrally with the reference convex portion 22 on the support side surface 21 a of the mounting base material 21. When the reference cylindrical surface 22a of the reference convex portion 22 is fitted to the cylindrical surface 4a of the positioning concave portion 4, the anti-rotation reference convex portion 23 is fitted into the anti-rotation concave portion 5 formed on the base 2 with a minimum gap. Can be combined.

  A shaft hole 24 is formed in the center of the reference convex portion 22 so as to penetrate the mounting base material 21 on the front and back sides. The inner peripheral surface 24a of the shaft hole 24 is a cylindrical surface having a certain radius with the support center line O2 as the center. As shown in FIG. 5, the inner diameter dimension of the inner peripheral surface 24a of the shaft hole 24 is Db.

  As shown in FIG. 5, the attachment base material 21 is formed with a holding recess 25 that is recessed from the operation side surface 21b. The inner peripheral surface 25a of the holding recess 25 is a cylindrical surface having a certain radius with the support center line O2 as the center. As shown in FIG. 5, the inner diameter of the inner peripheral surface 25a is Dc. A bearing member 26 is held in the holding recess 25. The bearing member 26 is a ball bearing or a metal bearing formed of a porous metal coated or impregnated with a lubricating oil. The outer peripheral surface 26 a of the bearing member 26 is press-fitted without any gap to the inner peripheral surface 25 a of the holding recess 25. Therefore, the rotation support portion 26b, which is the center hole of the bearing member 26, can be positioned substantially concentrically with the inner peripheral surface 25a of the holding recess 25.

  As shown in FIG. 5, a metal rotation shaft 28 is rotatably supported by the bearing member 26. The rotary shaft 28 has a support shaft portion 28a having a large outer diameter size and a small diameter portion 28b having a smaller outer diameter size than the support shaft portion 28a. The tip of the small diameter portion 28b is a non-circular connecting shaft portion 28c having a D-shaped cross section, and a flat portion 28d is formed on the connecting shaft portion 28c. The support shaft portion 28a is inserted into the rotation support portion 26b of the bearing member 26 with almost no gap, and the rotation shaft 28 is rotatably supported. When the bearing member 26 is a ball bearing, the support shaft portion 28a is press-fitted into the inner portion, and the rotary shaft 28 is rotatably supported together with the inner portion.

  As shown in FIG. 5, the small-diameter portion 28 b of the rotating shaft 28 is inserted into the shaft hole 24 of the mounting base material 21 with a slight gap, and the connecting shaft portion 28 c is further forward from the reference convex portion 22. Protruding to

  The reference convex portion 22, the shaft hole 24, and the holding concave portion 25 are formed by the same pair of molds when the mounting base material 21 is molded. The holding concave portion 25 and the shaft hole 24 are simultaneously molded by the convex portion of one mold, and the reference convex portion 22 is molded by the concave portion of the other mold. Therefore, the reference cylindrical surface 22a of the outer diameter dimension Da of the reference convex portion 22, the inner peripheral surface 24a of the inner diameter dimension Db of the shaft hole 24, and the inner peripheral surface 25a of the inner diameter dimension Dc of the holding recess 25 are all support centers. The positional deviation tolerance with respect to the line O2 is extremely small. Since the bearing member 26 is positioned with reference to the inner peripheral surface 25a of the holding recess 25, the positional deviation tolerance between the axis of the rotary shaft 28 supported by the bearing member 26 and the support center line O2 is also extremely small.

  As shown in FIG. 1, the attachment base material 21 is formed with a pair of female screw holes 27, 27 that open to the support side surface 21 a. When the mounting screw 38 is a self-tapping screw, a through hole in which no screw groove is formed is formed instead of the female screw holes 27 and 27.

  As shown in FIGS. 1 and 5, a printed wiring board 31 is installed between the mounting base material 21 and the rotary sensor 1.

  As shown in FIG. 1, the printed wiring board 31 has land portions 32a and 32b and land portions 33a and 33b formed on a surface 31a of an insulating substrate. Three extraction land portions 34, 34, 34 are formed on the lower surface of the printed wiring board 31. Two of the three extraction land portions 34, 34, 34 are individually connected to the land portion 32 a and the land portion 32 b through a wiring pattern (not shown), and the other one extraction land portion 34. However, it is electrically connected to both the land portions 33a and 33b. Although not shown, a connector is attached to the surface 31a of the printed wiring board 31, and each terminal of the connector is individually soldered to the three extraction land portions 34, 34, 34.

  As shown in FIG. 1, relief holes 35 are formed in the printed wiring board 31. The inner diameter dimension of the escape hole 35 is sufficiently larger than the outer diameter dimension Da of the reference cylindrical surface 22 a of the reference protrusion 22 formed in the mounting base material 21.

  The printed wiring board 31 is formed with a relief recess 36 a that continues upward from the relief hole 35 and a relief recess 36 b that continues downward from the relief hole 35. As shown in FIG. 2, the escape recess 36 a is formed in a size that allows the positioning pin 6 a protruding from the installation side surface 2 b of the base 2 of the rotary sensor 1 to be inserted with a sufficient gap. The escape recess 36b is formed in such a size that both the rotation preventing reference protrusion 23 formed on the mounting base material 21 and the positioning pin 6b formed on the base 2 can be inserted with a sufficient gap. .

  The printed wiring board 31 is provided with concave mounting holes 37 and 37. The male screw portion 38a of the mounting screw 38 can be inserted into the mounting holes 37, 37 with a sufficient gap.

  Next, an assembly method for configuring the detection device 20 by attaching the rotary sensor 1 assembled and completed as shown in FIGS. 1 and 2 to the attachment base material 21 will be described.

  The lead terminals 15a and 15b extending from the base 2 of the rotary sensor 1 are individually soldered to the land portions 32a and 32b, and the terminal portions 16b and 16c of the common lead terminal 16 are soldered to the land portions 33a and 33b. Thus, the rotary sensor 1 is fixed to the printed wiring board 31. At this time, the rotary sensor 1 and the printed wiring board 31 need only roughly match the center of the shaft coupling hole 8 of the rotor 7 and the center of the escape hole 35. 31 need not be aligned with each other with high accuracy.

  The rotary shaft 28 is rotatably supported by a bearing member 26 held by the mounting base material 21.

  The printed wiring board 31 is placed on the support side surface 21 a of the mounting base material 21, and the reference convex portion 22 and the rotation shaft 28 are positioned inside the escape hole 35 of the printed wiring board 31. And the positioning recessed part 4 formed in the base 2 of the rotation type sensor 1 is fitted to the reference cylindrical surface 22a which is the outer peripheral surface of the reference convex part 22, and the rotation prevention recessed part 5 of the base 2 is a detent reference. The projection 23 is fitted.

  As shown in FIG. 6, in the base 2 of the rotary sensor 1, the positioning recess 4, the rotation stopper recess 5, and the rotation support hole 3 are integrally molded by the protrusion provided in one mold to support the rotation. Since the rotor 7 is rotatably inserted into the hole 3 with almost no gap, the center of the cylindrical surface 4a of the positioning recess 4 and the center of the rotating shaft portion 7a formed in the rotor 7 (the rotation of the shaft coupling hole 8). The tolerance of misalignment with the center) is very small. In addition, the mounting base material 21 is integrally formed with the same cylindrical mold (a pair of molds) in which the reference cylindrical surface 22a that is the outer peripheral surface of the reference convex portion 22 and the inner peripheral surface 25a of the holding concave portion 25 are formed. A rotating shaft 28 is supported by a bearing member 26 held by 25 with no gap. Therefore, the positional deviation tolerance between the center of the reference cylindrical surface 22a and the axis of the rotary shaft 28 is extremely small.

  Therefore, when the positioning recess 4 formed on the base 2 of the rotary sensor 1 is fitted to the reference cylindrical surface 22a which is the outer peripheral surface of the reference protrusion 22, the rotation of the shaft coupling hole 8 of the rotor 7 is rotated. The center and the axis of the rotary shaft 28 can be made substantially coincident with each other, and the connecting shaft portion 28c of the rotating shaft 28 and the shaft connecting hole 8 of the rotor 7 can be fitted to each other with almost no axial deviation.

  Further, by fitting the rotation stopper recess 5 of the base 2 to the rotation prevention reference protrusion 23, the rotary sensor 1 and the mounting base material 21 can be positioned in accordance with the rotation phase with high accuracy.

  After the reference convex portion 22 and the non-rotating reference convex portion 23 are fitted to the positioning concave portion 4 and the non-rotating concave portion 5 to position the rotary sensor 1 on the mounting base material 21, the mounting screws 38 and 38 are printed. The detection device 20 is configured by inserting into the mounting holes 37 and 37 of the board 31 and screwing into the female screw holes 27 and 27 to complete the mounting of the rotary sensor 1 and the printed wiring board 31 to the mounting base material 21. Can do.

  In the detection device 20, the base 2 of the rotary sensor 1 is positioned directly on the mounting base material 21, and is supported on the center (rotation center) of the shaft coupling hole 8 of the rotor 7 and the mounting base material 21 side. Since the positional deviation of the rotating shaft 28 from the axis is very small, the rotating load when rotating the rotor 7 by rotating the rotating shaft 28 can be extremely lightened. Further, the center of the rotation locus of the detection sliding portion 17c of the slider 17 fixed to the rotor 7 and the center of the arc shape of the resistor layer 11 can be matched with high accuracy, and the rotation shaft 28 The linearity of the detected value can be maintained with high accuracy with respect to the rotation angle of the rotation.

  Further, since the rotation sensor 1 can be positioned in the rotation direction by fitting the rotation stopper concave portion 5 and the rotation prevention reference convex portion 23, the rotation phase when the rotation shaft 28 rotates and the resistor layer 11. It is possible to match the relative phase of the contact position with the detection sliding portion 17c with high accuracy.

  As shown in FIG. 2, the detection device 20 of the embodiment has a pair of positioning pins 6 a and 6 b protruding from the base 2. In the structure in which the mounting base material 21 having the structure shown in FIGS. 1 and 5 is used, the reference convex portion 22 and the positioning concave portion 4 formed on the base 2 are fitted to position the rotary sensor 1. The positioning pins 6a and 6b are not substantially used. When the rotary sensor 1 is positioned and attached to the printed wiring board without using the mounting base material 21, the positioning pins 6a and 6b are fitted into positioning holes formed in the printed wiring board, The positioning pins 6a and 6b are used for positioning. Further, the positioning pins 6a and 6b may be used for positioning the rotary sensor with respect to the printed wiring board when installed on the mounting base material 21.

  In the above-described embodiment, the holding recess 25 is formed in the mounting base material 21, and the rotation shaft 28 is supported by the bearing member 26 held in the holding recess 25, but the shaft hole 24 of the mounting base material 21. As a bearing portion, the rotary shaft may be directly supported by the shaft hole 24, or the bearing may be held in the shaft hole 24, and the rotary shaft may be supported by the bearing.

  When the shaft hole 24 serves as a bearing portion, a concave portion for forming the reference cylindrical surface 22a, which is the outer peripheral surface of the reference convex portion 22, is provided in one mold, and a convex for forming the shaft hole 24 in the other mold. By providing the portion and molding the mounting base material 21 with this mold, the centers of the reference cylindrical surface 22a and the shaft hole 24 can be formed with high accuracy.

  Further, in the present invention, the rotary sensor 1 may be installed directly on the support side surface 21 a of the mounting base material 21 without sandwiching the printed wiring board 31.

  Furthermore, the detection unit 10 used in the rotary sensor 1 is not limited to the one having the resistor layer, and the electrode unit is intermittently provided in the rotation direction, and the slider supported by the rotor 7 is an electrode. It may be a pulse input type encoder or the like that comes into contact with the parts in order.

DESCRIPTION OF SYMBOLS 1 Rotation type sensor 2 Base 3 Rotation support hole 3a Inner peripheral surface 4 Positioning recessed part 4a Cylindrical surface 5 Anti-rotation recessed part 7 Rotor 7a Rotating shaft part 8 Shaft coupling hole 10 Detection part 11 Resistor layer 12 Discontinuous part 13a, 13b Electrode layer 14 Common electrode layers 15a and 15b Lead terminal 16 Common lead terminal 17 Slider 17c Detection slide part 17d Common slide part 19 Cover member 20 Detector 21 Mounting base material 22 Reference convex part 22a Reference cylindrical surface 23 Non-rotating Reference convex portion 24 Shaft hole 25 Holding concave portion 25a Inner peripheral surface 26 Bearing member 28 Rotating shaft 28a Support shaft portion 28c Connection shaft portion 31 Printed wiring board 35 Escape hole 37 Mounting hole 38 Mounting screw

Claims (10)

In a rotary sensor having a base, a rotor rotatably supported by the base, and a detection unit for detecting the rotation of the rotor,
The base is formed of a synthetic resin, and a positioning recess that fits into the base is provided with a rotation support hole that rotatably supports the rotor and a reference convex provided on a mounting base on which the base is installed. And the inner peripheral surface of the positioning recess has a cylindrical surface having a diameter larger than the inner diameter of the rotation support hole, and the cylindrical surface and the inner peripheral surface of the rotation support hole Is formed in concentric circles.   2. The rotary sensor according to claim 1, wherein the rotation support hole and the positioning recess are formed by the same convex portion provided in the mold.   The rotation type sensor according to claim 1 or 2, wherein the base is formed with a rotation stopper recess extending in a radial direction from the center of the positioning recess continuously with the cylindrical surface. The detection unit includes a resistor layer provided on the base and a conductive slider provided on the rotor and sliding on the surface of the resistor layer;
The resistor layer is provided on a surface of the base opposite to the surface on which the positioning recess is provided, and the resistor layer is an arc portion along an arc locus centering on a rotation center line of the rotor. The rotary sensor according to claim 1, wherein the arc portion is formed at a position not overlapping the positioning recess. The detection unit includes a resistor layer provided on the base and a conductive slider provided on the rotor and sliding on the surface of the resistor layer;
The resistor layer is provided on a surface of the base opposite to the surface on which the positioning recess is provided, and the resistor layer is an arc portion along an arc locus centering on a rotation center line of the rotor. And a discontinuous part in which a part of the arc part is interrupted,
The rotary sensor according to claim 3, wherein the arc portion is formed at a position that does not overlap the positioning recess, and the discontinuous portion is formed at a position that overlaps the rotation stopper recess.   The rotary sensor according to claim 1, wherein the base is provided with a terminal portion that conducts to the detection portion. In the detection apparatus which has a rotation type sensor according to any one of claims 1 to 6, and a mounting base material to which the rotation type sensor is attached,
The mounting base material is formed of a synthetic resin, and the mounting base material is provided with a reference convex portion and a bearing portion that supports a rotating shaft that passes through the center of the reference convex portion, and an outer peripheral surface of the reference convex portion And the inner peripheral surface of the bearing portion are formed concentrically,
The detecting device, wherein the rotating shaft is coupled to the rotor in a state where the positioning concave portion is fitted to the reference convex portion.   The detection device according to claim 7, wherein an inner peripheral surface of the bearing portion is formed by a convex portion of one mold, and an outer peripheral surface of the reference convex portion is molded by a concave portion of the other mold.   A printed wiring board is provided between the mounting base material and the base, and a relief hole through which the reference convex portion is inserted through a gap is formed in the printed wiring board. The detection device according to claim 7 or 8, wherein the provided terminal portion is soldered to a land portion of the printed wiring board, and the printed wiring board is fixed to the mounting base material.   A mounting hole is opened in the printed wiring board, a mounting screw is inserted into the mounting hole with a gap, and the mounting screw is screwed into a hole formed in the mounting base material. The detection device according to claim 9, wherein a wiring board is fixed to the mounting base material.

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