JP2017110982A - Eddy current type instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an eddy current type instrument that prevents the occurrence of malfunction of an integrator due to a change in temperature and a change over time even when a synthetic resin-made frame is used.SOLUTION: The eddy current type instrument 10 is an eddy current type instrument comprising a rotor, an integrator 12 that rotates a character wheel on the basis of the rotation of the rotor to display a travel distance, and a housing 40 that rotatably pivotally supports the rotor and character wheel; and the housing 40 is provided with an elastic piece 72 that is applied with a thermoplastic synthetic resin, in contact with a rotational shaft 17 of the character wheel, and presses the rotational shaft 17, and a piece part 71a that holds the rotational shaft 17.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an eddy current type instrument.

  A vehicle is usually equipped with instruments such as a speedometer and a tachometer. As these instruments, there is known an eddy current type instrument in which a pointer is rotated by an eddy current generated when a magnet is rotated. As a conventional technique related to an eddy current type instrument, there is a technique disclosed in Patent Document 1.

  As shown in Patent Document 1, an eddy current type instrument has a base, a lid placed on the base, a first rotary shaft rotatably supported on the base, and the first rotary shaft. A magnet that is attached and rotates together with the first rotation shaft, a second rotation shaft that is rotatably attached to the lid, and rotation by an eddy current that is generated when the magnet is supported by the second rotation shaft. And a damper mechanism for suppressing rapid rotation of the second rotating shaft and the rotor. The pointer visually recognized by the occupant is provided at the upper end of the second rotation shaft.

  An accumulator comprising a plurality of character wheels for displaying the total travel distance and section distance is attached by being crimped to a metal frame.

JP 2000-162225 A

  To reduce material costs and manufacturing costs, the metal frame was replaced with a synthetic resin frame, and the rotating shaft of the character wheel was held between the welds. For the purpose of preventing falsification, the welded part is thinner and more fragile than other parts, so the welded part is deformed due to temperature changes and secular changes, resulting in displacement of the rotation axis of the character wheel, abnormal noise, There was a risk of causing malfunction.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an eddy current type instrument having a synthetic resin frame that is unlikely to cause malfunction of the integrator due to temperature change or aging.

  The eddy current measuring instrument 10 according to the present invention includes a rotating body 23, an accumulator 12 that displays the travel distance by rotating the character wheel 12a based on the rotation of the rotating body 23, the rotating body 23, and the character wheel 12a. An eddy current type instrument having a casing 40 that pivotally supports the casing 40. The casing 40 is made of a thermoplastic synthetic resin material and abuts against the rotating shaft 17 of the character wheel 12a. An elastic piece 72 that presses the rotating shaft 17 and a piece portion 71a that holds the rotating shaft 17 are provided.

  The tip of the piece 71a is heat-sealed so as to cover the rotating shaft 17.

  The elastic piece 72 and the piece portion 71 a are provided on one end side of the rotating shaft 17.

  The elastic piece 72 has a hook shape that engages with the rotating shaft 17 and is supported by the U-shaped groove portion 71 continuously formed from the piece portion 71 a and the rotating shaft 17.

  A direction in which the elastic piece 72 is engaged with the rotating shaft 17 and a welding portion of the piece 71a are provided in the same direction.

  According to the present invention, even if a temperature change or a secular change occurs using a frame made of a synthetic resin, an eddy current type instrument that does not cause malfunction of the integrator can be obtained.

It is a side view of an eddy current type instrument showing one embodiment of the present invention. It is sectional drawing of the state which looked at the eddy current type instrument shown by FIG. 1 from the left side. It is a principal part enlarged view of the eddy current type meter shown by FIG. It is the figure of the state which looked at the eddy current type instrument shown by FIG. (A) Enlarged view of the main part immediately after placing the accumulator around the protrusion shown in FIG. 4, (b) Enlarged view of the main part after fixing the accumulator, (c) After fixing the accumulator (with the protrusion It is a principal part enlarged view of the case of welding. It is a principal part enlarged view of a piece part, an elastic piece, and a shaft.

  Hereinafter, an eddy current instrument according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the description, left and right refer to the left and right with reference to the occupant of the motorcycle, and front and rear refer to the front and rear with reference to the traveling direction of the motorcycle. In the figure, Fr indicates the front, Rr indicates the rear, Le indicates the left when viewed from the occupant, Ri indicates the right when viewed from the occupant, Up indicates the upper side, and Dn indicates the lower side.

  FIG. 1 shows an instrument body (eddy current instrument) 10 of an eddy current instrument according to the present invention as viewed from the left side. A pointer 11 and a cover are attached to the instrument body 10, and are mounted on a two-wheeled vehicle, for example, and used as a vehicle speedometer. An accumulator 12 for displaying the accumulated travel distance is provided in front of a rotation shaft (second rotation shaft) 45 to which the pointer 11 is attached. The pointer 11 and the accumulator 12 operate in conjunction with the rotation of the front wheel of the motorcycle. Hereinafter, the details of the meter body 10 will be described.

  The meter body 10 includes a bearing body 20, a base 30 into which the bearing body 20 is inserted, a lid (housing) 40 that covers the base 30, and parts that are provided on the base 30 and the lid 40. It consists of.

  The accumulator 12 is inserted through a shaft (rotating shaft) 17 and rotates a plurality of character wheels 12a on which numerical values are printed via a gear according to rotation of a first rotating shaft (rotating body) 23 described later. Thus, the distance traveled can be expressed numerically.

  The bearing body 20 includes a cylindrical member 21 and a sintered bearing 22 made of sintered metal provided on the inner periphery of the cylindrical member 21. A first rotary shaft 23 is rotatably provided on the inner periphery of the slide bearing 22.

  The base 30 is configured, for example, by press forming a common cold rolled steel plate (SPCC). An insertion hole 31 is formed in the center of the base 30. A ring member 32 is provided on the periphery of the cylindrical member 21. The cylindrical member 21 and the base 30 are fixed by crimping the ring member 32 after inserting the ring member 32 into the insertion hole 31.

  A cup-shaped magnetic conductor 24 and a donut-shaped magnet 25 are fixed to the upper portion of the first rotating shaft 23. That is, the magnetic conductor 24 and the magnet 25 can rotate together with the first rotating shaft 23. The magnetic conductor 24 opens upward. The magnet 25 is disposed so as to be accommodated in the magnetic conductor 24 opened upward. As the magnet 25, for example, a radially magnetized sintered magnet made of Al-Ni-Co is used. The upper end of the first rotating shaft 23 is beaten downward, and a second bearing 26 is disposed at the beaten portion.

  A horizontal shaft 15 that meshes with the first rotating shaft 23 is provided below the magnetic conductor 24. The horizontal shaft 15 is rotatably supported by the base 30 (see FIG. 1). The horizontal axis 15 is orthogonal to the first rotation axis 23 and constitutes a part of the gear mechanism 16 that transmits the rotation of the first rotation axis 23 to the accumulator. The gear mechanism 16 employs a known technique such as a worm gear. Detailed description is omitted.

  The lid body 40 is, for example, an injection-molded product by injection molding, and includes a wall portion 41 that extends upward from an end portion of the base portion 30 and a ceiling portion 42 that covers an upper portion surrounded by the wall portion 41. The lid 40 can employ polybutylene terephthalate resin (PBT). The ceiling portion 42 is formed with a housing portion 43 for housing the accumulator 12 from substantially the center to the front portion.

  A circular support hole 44 is formed on the axis CL of the first rotating shaft 23 at the approximate center of the ceiling portion 42. That is, the second rotation shaft 45 is disposed on the same axis line CL as the first rotation shaft 23. The second rotation shaft 45 is rotatably supported by the lid body 40 in a state in which the second rotation shaft 45 is in contact with the inner peripheral surface of the support hole 44. The lower end of the second rotating shaft 45 is rotatably supported by the second bearing 26.

  A synthetic resin rotor support 50 is attached to the second rotating shaft 45. Details of the rotor support 50 will be described later. The rotor 60 supported by the rotor support portion 50 is made of a nonmagnetic metal, for example, aluminum, and is configured in a cup shape by press molding. The cylindrical wall portion of the rotor 60 is located between the magnet 25 and the magnetic conductor 24.

  Above the ceiling portion 42, a whisker spring 46 that biases the second rotating shaft 45 is provided. The whisker spring 46 is hooked on a hook 47 whose center is fixed to the second rotating shaft 45 and whose end is fixed to the ceiling 42. The end is fixed by, for example, heat caulking. The whisker spring 46 biases the second rotating shaft 45 in a direction opposite to the direction of rotation of the rotor 60 due to eddy current.

  The lid 40 is provided with a left-side integrator support unit 70 and a right-side integrator support unit 80 that support both ends of the shaft (rotating shaft) 17 of the integrator 12.

  The right integrator support unit 80 includes a shaft hole (not shown) that supports one end of the shaft 17. The left integrator support portion 70 extends in the vertical direction to support the other end of the shaft 17, and presses the U-shaped groove portion 71 and the shaft 17 supported by the shaft hole against the U-shaped groove portion 71. An elastic piece 72 is provided.

  The left integrator support portion 70 is provided with a protruding portion (one portion) 71a along the direction in which the U-shaped groove portion 71 extends. The protrusion 71a is formed thinner than other parts. After the integrating meter 12 is placed from above the U-shaped groove 71, the tip of the protrusion 71a is thermally deformed so that the gap Wd of the protrusion 71a is narrower than the diameter Dd of the shaft 17. FIG. 5A shows a state around the protrusion 71a when the accumulator 12 is placed, and FIGS. 5B and 6 show a state around the protrusion 71a after thermal deformation.

  By adopting such a structure, the shaft 17 can be firmly supported by the protrusion 71a. Further, when the elastic piece 72 is pressed against the shaft 17, there is no backlash, and the malfunction of the integrator due to generation of abnormal noise or malfunction is not generated. When the projecting portion 71a is thermally processed, the shaft 17 can be processed in a state where it is properly positioned by the elastic piece 72, so that the shaft 17 can be pivotally supported at an optimal position where no abnormal noise or malfunction occurs. The eddy current type instrument is reliable with no variations in products.

  By providing the elastic piece 72 and the protruding portion 71 a on one end side of the shaft 17, the integrator 12 can be prevented from being attached and detached. When the accumulator 12 is removed and tampered with, it is possible to identify the tampering marks of the accumulator 12 due to the presence or absence, breakage, or deformation of the protruding portion 71a, so that unauthorized modification or tampering can be suppressed.

  The direction in which the elastic piece 72 is engaged with the shaft 17 and the tip portion of the protrusion 71a that is thermally deformed are provided in the same direction (Up side), so that the product is directed in the same direction in the manufacturing process. Since the integrator 12 can be assembled and held as it is, it is effective and the assembly process can be automated.

  The instrument body 10 includes a damper mechanism 19 for suppressing rapid rotation of the second rotating shaft 45 and the rotor 60. Hereinafter, the damper mechanism 19 will be described.

  The damper mechanism 19 includes an oil cup 52 that is filled with oil 51 and is rotatable together with the second rotating shaft 45, a resistance portion 49 that extends from the lid body 40 to the oil cup 52, and a tip portion 48 is immersed in the oil 51. Have.

  In the center of the rotor 60, an insert hole 61 for insert-molding the rotor support portion 50 is formed. The upper edge 62 that is the edge on the upper surface side of the insert hole 61 is chamfered.

  The rotor support portion 50 includes a lower surface portion 53 that supports the lower surface side of the rotor 60, a main body portion 54 that extends from the center of the lower surface portion 53 along the second rotation shaft 45, and an upper surface that supports the upper surface side of the rotor 60. Part 55. From the upper surface portion 55, a support portion reinforcing portion 58 extends upward along the second rotation shaft 45.

  The oil cup 52 has a cylindrical shape and is integrally provided on the upper surface portion 55 of the rotor support portion 50.

  The oil cup 52 is surrounded by an oil reservoir 56 that accumulates oil spilled from the oil cup 52. The oil reservoir 56 has an annular groove 56 a for storing oil, and is integrally provided on the upper surface 55 of the rotor support 50. The oil reservoir 56 is provided on the edge of the upper surface 55 of the rotor support 50.

  In the present embodiment, the oil reservoir 56 and the annular groove 56a are formed by extending the edge of the upper surface portion 55 upward. For example, the upper surface portion is located closer to the inner periphery than the edge of the upper surface portion 55. An oil reservoir and an annular groove may be formed by forming an annular recess in 55.

  The width W1 of the annular groove 56a is smaller than the distance D from the tip of the oil reservoir 56 to the lid body 40.

  The resistance portion 49 is formed integrally with the lid body 40. The distal end portion 48 of the resistance portion 49 extends to the vicinity of the upper surface portion 55 of the rotor support portion 50. The distal end portion 48 is provided so as to surround the support portion reinforcing portion 58.

  A width W2 from the resistance portion 49 to the second rotation shaft 45 includes a portion wider than a width W3 from the distal end portion 48 of the resistance portion 49 to the support portion reinforcement portion 58. Similarly, a width W2 from the resistance portion 49 to the second rotation shaft 45 includes a portion wider than a width W4 from the tip portion 48 to the oil cup 52.

  When the two-wheeled vehicle travels, the first rotating shaft 23 rotates in conjunction with the rotation of the front wheel, and the magnetic conductor 24 and the magnet 25 fixed to the first rotating shaft 23 rotate integrally. Due to the rotation of the magnet 25, an eddy current is generated in the rotor 60 and the rotor 60 rotates. The pointer (see FIG. 1) is displaced by the rotation of the rotor 60. As the speed of the motorcycle increases, the rotational speed of the magnet 25 increases and the eddy current generated in the rotor 60 also increases. As the eddy current increases, the rotational speed of the rotor 60 also increases, and the force for rotating the pointer also increases. The pointer 11 stops at a position that balances the urging force of the whisker spring 46. The occupant can visually recognize the traveling speed based on the position indicated by the pointer 11.

  Similarly, the rotation of the first rotating shaft 23 is transmitted to the accumulator 12 via the gear mechanism 16. The occupant can visually recognize the distance traveled by the numbers indicated on the accumulator 12.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, in the present embodiment, an example in which the gap Wd of the protruding portion 71a is narrowed after placing the accumulator 12 has been described. However, as shown in FIG. It can be welded.

  In the present embodiment, the right-hand integrator support portion 80 is provided with a shaft hole. However, the left-hand integrator support portion 70 may have the same structure, or the left and right integrator-support portions may be reversed. There is no problem.

  The accumulator 12 is provided above the second rotating shaft 45 (the traveling direction of the two-wheeled vehicle), but may be provided below the second rotating shaft 45 (on the driver side).

  Further, by providing the elastic piece and the holding portion (protruding portion) with a fragile portion that is thinner than the portion in contact with the rotating shaft of the accumulator, an anti-tampering effect can be expected.

  The eddy current type instrument of the present invention is also suitable as a speedometer for automobiles, agricultural machines, construction machines, ships, and the like.

10 Instrument body (eddy current type instrument)
11 Pointer 12 Accumulator 12a Dial wheel 15 Horizontal axis 16 Gear mechanism 17 Shaft (Rotary axis)
DESCRIPTION OF SYMBOLS 19 Damper mechanism 20 Bearing body 21 Cylindrical member 22 Sliding bearing 23 1st rotating shaft (rotating body)
24 Magnetic Conductor 25 Magnet 26 Second Bearing 30 Base 31 Insertion Hole 32 Ring Member 40 Lid (Housing)
41 Wall portion 42 Ceiling portion 43 Housing portion 44 Support hole 45 Second rotation shaft 46 Spring 47 Hook 48 Tip portion 49 Resistance portion 50 Rotor support portion 51 Oil 52 Oil cup 53 Lower surface portion 54 Main body portion 55 Upper surface portion 56 Oil reservoir portion 56a annular groove 58 support part reinforcement part 59 boundary part 60 rotor 61 insert hole 62 upper edge 70 left side accumulator support part 71 U-shaped groove part 71a protrusion part (single part)
72 Elastic piece 80 Right side accumulator support part Dd Diameter of shaft 17 Wd Clearance of protruding part

Claims (5)

A rotating body; an accumulator that displays a travel distance by rotating the character wheel based on the rotation of the rotating member; and a housing that pivotally supports the rotating member and the character wheel. An eddy current instrument,
The casing is made of a thermoplastic synthetic resin material,
An elastic piece that abuts the rotation shaft of the character wheel and presses the rotation shaft;
An eddy current type instrument comprising a piece for holding the rotating shaft.   The eddy current type instrument according to claim 1, wherein the tip of the one piece is heat-welded so as to cover the rotating shaft.   The eddy current instrument according to claim 1, wherein the elastic piece and the piece are provided on one end side of the rotating shaft.   The said elastic piece is a hook shape latched to the said rotating shaft, and supports the U-shaped groove part continuously formed from the said piece part, and the said rotating shaft on both sides. Item 3. The eddy current type instrument according to item 2. The eddy current type instrument according to claim 4, wherein a direction in which the elastic piece is engaged with the rotating shaft and a welding position of the piece are provided in the same direction.

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