JP2006214871A - Detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detector having a mechanism section driven by a detected object and a circuit section for generating a detection signal according to the driving state of the mechanism section, and can perform an accurate detection operation. <P>SOLUTION: The detector has the mechanism section driven by the detected object and the circuit section for detecting an operation of the mechanism section in a non-contact manner. The detector also has an isolating section for isolating the mechanism section from the circuit section. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a detection apparatus, and more particularly, to a detection apparatus having a mechanism unit driven by a detection target and a circuit unit that generates a detection signal corresponding to the driving state of the mechanism unit.

  A rotation detection device that detects a rotation angle has been developed using a magnetoresistive element. The magnetoresistive element is an element whose resistance value changes according to the strength of the surrounding magnetic field.

  A rotation detection device using a magnetoresistive element is provided with a magnet in a rotation drive mechanism, and a magnetoresistive element is arranged opposite to the magnet to detect the resistance value of the magnetoresistive element that changes according to the strength of the magnetic field of the magnet. It is an apparatus which detects rotation of a magnet by doing (patent documents 1-5).

Japanese Patent Laid-Open No. 04-066813 Japanese Patent Laid-Open No. 02-298814 Japanese Patent Application Laid-Open No. 08-12201 Japanese Patent Laid-Open No. 08-178612 JP-A-11-014644

  However, in the conventional rotation detection device, since the circuit unit and the rotation drive mechanism unit are stored in the same storage unit by the case, if water or dust enters from the gap between the rotation drive mechanism unit and the case, the circuit unit and the rotation drive mechanism unit have entered. There is a problem that moisture or dust adheres to the wiring of the circuit portion, the wiring is short-circuited, the resistance value is changed, and the accurate detection cannot be performed.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a detection device capable of performing an accurate detection operation.

  The present invention provides a detection device having a mechanism portion (112) driven by a detection target and a circuit portion (111) for detecting the operation of the mechanism portion (112) in a non-contact manner, and the mechanism portion (112) and the circuit. It has the isolation | separation part (123) which isolates a part (111).

  The isolation part (123) is constituted by a circuit part storage case for storing the circuit part (111).

  The circuit unit storage case includes a case main body (123) that stores the circuit unit (111) and a cover (124) that closes the opening of the case main body (123), and the case main body (123) is covered by the cover (124). Is sealed.

  The mechanism part (112) has a rotating shaft (151) that rotates relative to the circuit part (111), and the isolation part (123) has a bearing part (137) of the rotating shaft (151).

  The mechanism portion (112) has a mechanism portion storage case (154) that engages with the circuit portion storage case (123) and has a rotation shaft (151) rotatably held therein.

  In addition, the said reference code is a reference to the last, and a claim is not limited by this.

  According to the present invention, the mechanism portion and the circuit portion are isolated from each other by the isolation portion, so that the circuit portion can be protected from moisture and dust.

〔overall structure〕
1 is an exploded perspective view of an embodiment of the present invention as viewed from above, FIG. 2 is an exploded perspective view of the embodiment of the present invention as viewed from below, and FIG. 3 is an assembly of the embodiment of the present invention. FIG. 4 is a plan view of the embodiment of the present invention during assembly, and FIG. 5 is a sectional view of the embodiment of the present invention.

  The rotation detection device 100 according to this embodiment includes a circuit unit 111 and a drive mechanism unit 112. The circuit unit 111 generates an electrical signal corresponding to the driving operation of the driving mechanism unit 112. The drive mechanism unit 112 is driven in accordance with an external drive operation, and performs a magnetic action on the circuit unit 111 in accordance with the drive operation.

[Circuit part 111]
The circuit unit 111 includes a magnetoresistive element IC 121, a printed wiring board 122, a case body 123, a cover 124, and a cable 125.

  The magnetoresistive element IC 121 has four magnetoresistive elements arranged in four directions from the approximate center thereof, and is soldered to the approximate center of the surface of the printed wiring board 122 on the arrow Z1 direction side. A magnetoresistive element is an element whose resistance changes according to the magnitude of the surrounding magnetic field.

  In addition to the magnetoresistive element IC 121, various electronic components are mounted on the printed wiring board 122, and a cable 125 is soldered to one side of the peripheral portion.

  The cable 125 supplies power to the printed wiring board 122 and outputs detection signals generated by the mounted magnetoresistive element IC 121 and various electronic components to the outside.

  The printed wiring board 122 is housed in the housing portion 131 of the case body 123. Engagement protrusions 132 are formed on the peripheral edge of the storage part 131 of the case body 123. The printed wiring board 122 is positioned in the case main body 123 with the peripheral edge of the surface on the arrow Z1 direction side engaging with the engaging protrusion 132.

  A recess 133 is formed on the bottom surface of the storage part 131 of the case body 123. The recess 133 is formed by reducing the thickness of the inner surface of the case main body 123 in the arrow Z1 direction toward the arrow Z1 direction. When the printed wiring board 122 is accommodated in the case body 123, the magnetoresistive element IC 121 is fitted into the recess 133.

  The opening surface of the case body 123 is closed by the cover 124. The cover 124 is formed with an engaging projection 141 at the peripheral edge of the surface in the direction of the arrow Z1. When the cover 124 is engaged with the case main body 123, the engagement convex portion 141 comes into contact with the surface on the arrow Z <b> 2 direction side of the printed wiring board 122. Further, a notch 134 is formed on the side surface of the case main body 123 in the direction of the arrow X2 and the end in the direction of the arrow Z2. A cable 125 extending from the printed wiring board 122 is engaged with the notch 134. The cable 125 is extended to the outside through the notch 134.

  The printed wiring board 122 is held between the engagement convex portion 132 of the case main body 123 and the engagement convex portion 141 of the cover 124 and is held inside the storage portion 131 of the case main body 123. Note that the case main body 123 and the cover 124 are bonded together by welding, a sealing material, an adhesive, or the like. Further, the notch 134 is sealed with a sealing material or a packing member. Thereby, the storage part 131 in which the printed wiring board 122 is stored is in a sealed state.

  Further, a convex portion 135 and a screw hole 136 are formed on the surface of the case main body 123 on the arrow Z1 direction side. The convex portion 135 and the screw hole 136 are used for positioning and mounting of the drive mechanism portion 112. A sliding convex portion 137 on which the drive mechanism 112 slides is formed on the surface of the case main body 123 facing the drive mechanism 112 in the direction of the arrow Z1. The sliding convex portion 137 is formed in an annular shape around the back surface position of the concave portion 133, and the drive mechanism portion 112 abuts slidably.

[Drive mechanism 112]
The drive mechanism 112 includes a rotation shaft 151, a magnet 152, a cap 153, an upper cover 154, and a screw 155.

  FIG. 6 is a perspective view of the rotation shaft portion 151, and FIG. 7 is a configuration diagram of the rotation shaft portion 151.

  The rotating shaft 151 is formed by molding resin, and includes a shaft portion 161 and a holding portion 162. The shaft portion 161 is supported by the upper cover 154. An arrow Z1 direction and an end portion of the shaft portion 161 are extended to the outside from the upper cover 154 in the arrow Z1 direction. A cutout portion 170 is formed in a portion extending to the outside of the shaft portion 161. The notch 170 positions the rotary shaft 151 in the rotational direction and the arrow θ direction.

  The holding part 162 is formed at the end of the shaft part 161 in the arrow Z2 direction. The holding part 162 is formed in a columnar shape larger than the outer diameter of the shaft part 161, and a notch part 171 is formed in a part facing each other. A claw 172 is formed in the notch 171. The claw portion 172 locks the cap 153.

  Further, a sliding portion 176 is formed around the shaft portion 161 on the end surface of the holding portion 162 in the arrow Z1 direction. The sliding part 176 hits the upper case 154 and slides.

  A holding hole 173 is formed on the end surface of the holding portion 162 in the arrow Z2 direction. The magnet 152 is engaged with the holding hole 173. The holding hole 173 is formed in a substantially rectangular shape, and a slit portion 174 and a hole portion 175 are formed around the holding hole 173.

  The slit portion 174 is formed along the outer side of the holding hole 173 and along the side wall, and is configured so that the side wall of the holding hole 173 can be bent outward, in the directions of arrows X1, X2, Y1, and Y2. Yes. The hole portions 175 are formed at the four corners of the holding hole 173, engage with the corner portions of the magnet 152 to position the magnet 152, and are used as relief when the side wall of the holding hole 173 is bent. .

  Note that the size of the holding hole 173 is formed to be substantially the same as or slightly smaller than the size of the magnet 152.

  The magnet 152 is held by the holding portion 162 by press-fitting the magnet 152 into the holding hole 173. In addition, after the magnet 152 is held in the holding hole 173, the cap 153 is locked to the holding portion 162.

  The magnet 152 is magnetized so that magnetic poles appear in the directions of arrows X1, X2 or Y1, Y2.

  FIG. 8 shows a perspective view of the cap 153.

  The cap 153 includes a holding surface portion 181 and a locking portion 182. The holding surface portion 181 extends in parallel to the bottom surface of the holding portion 162. A concave portion 183 into which the magnet 152 is fitted is formed in a portion of the holding surface portion 181 facing the magnet 152. A magnet 152 is fitted into the recess 183 to support the surface of the magnet 152 in the arrow Z2 direction from the arrow Z1 direction. A through hole 184 is formed at the center of the recess 183.

  A sliding portion 185 is formed in an annular shape around the recess 183 on the surface of the holding surface portion 181 in the arrow Z2 direction. The sliding portion 185 slides in contact with a sliding convex portion 137 provided on the surface of the case main body 123 of the circuit portion 111 on the arrow Z1 direction side. The depth of the sliding portion 185 and the height of the sliding convex portion 137 are such that when the sliding portion 185 and the sliding convex portion 137 which are thick portions abut each other, the bottom surface of the thin portion concave portion 183 and the case main body 123. The upper surface of the recess 132 is set so as not to contact.

  The upper case 154 has a configuration in which a resin is molded, and includes an accommodating portion 191, a bearing portion 192, a concave portion 193, an engaging concave portion 194, and a through hole 195.

  The storage unit 191 stores the holding unit 162. The bearing portion 192 has a cylindrical shape and is provided so as to protrude from the upper surface of the upper case 154 in the arrow Z1 direction. An end portion of the shaft portion 161 of the rotation shaft portion 151 in the arrow Z1 direction is inserted into the bearing portion 192 from the arrow Z2 direction side toward the arrow Z1 direction.

  A concave portion 193 having a diameter slightly larger than the inner diameter of the bearing portion 192 and slightly smaller than the outer diameter of the sliding portion 176 is formed around the bearing portion 192 on the bottom surface of the storage portion 191. Accordingly, a part of the sliding portion 176 comes into contact with the bottom surface of the storage portion 191 and slides. By adjusting the sliding area between the sliding portion 176 and the bottom surface of the storage portion 191, the friction between the rotating shaft portion 151 and the upper case 154 can be adjusted.

  In addition, an engagement recess 194 is provided on the bottom surface of the upper case 154 and on the peripheral edge on the arrow Z2 direction side at a position facing the protrusion 135 provided on the case body 123 of the circuit unit 111. The upper case 154 can be positioned with respect to the case main body 123, that is, the circuit portion 111 by fitting the engagement concave portion 194 to the convex portion 135 formed in the case main body 123. In addition, a through hole 195 is formed in the peripheral portion of the upper case 154 at a position facing the screw hole 136 provided in the case main body 123 of the circuit unit 111.

  A screw 155 passes through the through hole 195 from the upper surface of the upper case 154 and the arrow Z1 direction side. The screw 155 is screwed into the screw hole 136 of the case main body 123. The upper case 154 is fixed to the circuit unit 111 by screwing the screws 155 into the screw holes 136 of the case main body 123. By fixing the upper case 154 to the circuit unit 111, the holding part 162 of the rotating shaft part 151 is rotatably held between the upper surface of the case body 123 and the bottom surface of the upper case 154.

  At this time, by inserting a sealing material or packing between the joints of the upper case 154 and the case main body 123, the rotation mechanism 112 can be substantially sealed and rotated from moisture or dust. The mechanism 112 can be protected.

  Further, by filling the recess 193 with grease or lubricating oil, it can act as a sump, and by acting as a sump, entry of moisture and dust can be blocked.

〔effect〕
According to the present embodiment, since the storage portion of the circuit unit 111 and the rotation drive mechanism unit 112 can be isolated, moisture, dust, etc. can be prevented from entering the circuit unit 111 from the rotation drive mechanism unit 112, Therefore, malfunction of the circuit unit 111 can be prevented.

  In addition, since the rotation shaft 151 can be held between the upper case 154 and the case main body 123 constituting the circuit unit 111 and the rotation shaft 151 can be rotatably held, the configuration of the rotation drive mechanism 112 is simplified. And can be miniaturized.

It is the disassembled perspective view seen from the upper direction of one Example of this invention. It is the disassembled perspective view seen from the lower direction of one Example of this invention. It is a perspective view at the time of the assembly of one Example of this invention. It is sectional drawing of one Example of this invention. It is sectional drawing of one Example of this invention. FIG. 6 is a perspective view of a rotary shaft 151. FIG. 3 is a configuration diagram of a rotating shaft 151. It is a perspective view of a cap 153. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Rotation detection apparatus 111 Circuit part, 112 Rotation drive mechanism part 121 Magnetoresistive element IC, 122 Printed wiring board, 123 Case main body 124 Cover, 125 Cable 131 accommodating part, 132 Engaging convex part, 133 Concave part, 134 Notch part, 135 Engaging convex part 136 Concave part, 137 Sliding convex part 141 Engaging convex part 151 Rotating shaft part, 152 Magnet, 153 Cap, 154 Upper case, 155 Screw 161 Shaft part, 162 Holding part 171 Notch part, 172 Claw part 181 Holding Surface part, 182 Locking part, 183 Recessed part, 184 Through hole 191 Storage part, 192 Bearing part, 193 Recessed part, 194 Engaging recessed part, 195 Through hole

Claims (5)

In a detection device having a mechanism unit driven by a detection target and a circuit unit for detecting the operation of the mechanism unit in a non-contact manner,
A detection apparatus comprising an isolation part that isolates the mechanism part and the circuit part.   The detection device according to claim 1, wherein the isolation unit includes a circuit unit storage case that stores the circuit unit. The circuit unit storage case has a case main body for storing the circuit unit, and a cover for closing the opening of the case main body,
The detection apparatus according to claim 2, wherein the case main body is sealed with the cover. The mechanism unit has a rotation shaft that rotates with respect to the circuit unit,
The detection device according to claim 1, wherein the isolation part includes a bearing part of the rotating shaft.   The detection device according to claim 4, wherein the mechanism unit includes a mechanism unit storage case in which an opening is engaged with the circuit unit storage case and the rotation shaft is rotatably held therein.

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