JP6748926B2 - Eddy current instrument - Google Patents

Description

The present invention relates to an eddy current instrument having a damper mechanism.

Many vehicles such as two-wheeled vehicles are equipped with measuring instruments such as a speedometer and a tachometer. As these measuring instruments, there are known eddy current type measuring instruments in which a magnet is rotated in association with rotation of a front wheel and an indicator is rotated by an eddy current generated by the rotation of the magnet. As a conventional technique related to the eddy current instrument, there is a technique disclosed in Patent Document 1.

In the technique disclosed in Patent Document 1, an eddy current instrument has a substantially U-shaped base portion, a first rotation shaft rotatably supported by the base portion, and a first rotation shaft attached to the first rotation shaft. A magnet that rotates together with the first rotating shaft, a lid that covers the base, a second rotating shaft that is rotatably attached to the lid, and a support portion that is attached to the second rotating shaft. The rotor includes a rotor supported by the support unit and rotated by an eddy current generated by rotation of the magnet, and a damper mechanism for suppressing rapid rotation of the second rotation shaft and the rotor. The pointer visually recognized by the occupant is provided at the upper end of the second rotating shaft.

If the number of parts of such an eddy current instrument can be reduced, it is preferable that the eddy current instrument can be manufactured at low cost.

JP, 2000-162225, A

An object of the present invention is to provide an eddy current type instrument having a smaller number of parts.

According to the invention of claim 1, a base portion, a first rotation shaft rotatably supported by the base portion, a magnet attached to the first rotation shaft and rotating with the first rotation shaft, A lid that covers the base, a second rotation shaft that is rotatably attached to the lid, a resin-made support portion that is attached to the second rotation shaft, and the magnet that is supported by the support portion. An eddy current instrument having a rotor rotated by an eddy current generated by the rotation of the rotor and a damper mechanism for suppressing abrupt rotation of the second rotation shaft and the rotor
The damper mechanism includes an oil cup that is filled with oil and is rotatable with the second rotating shaft, and a resistance portion that extends from the lid body to the oil cup and has a tip end immersed in the oil. ,
The oil cup is integrally provided on the upper surface of the support portion ,
The support portion reinforcing portion extends upward from the upper surface portion of the support portion along the second rotation axis;
The tip portion of the resistance portion is provided so as to surround the support portion reinforcing portion,
An eddy current instrument characterized in that a width from the resistance portion to the second rotation axis includes a portion wider than a width from a tip end portion of the resistance portion to the support portion reinforcement portion. Provided.

As described in claim 2, preferably, the oil cup is surrounded by an oil reservoir for storing the oil spilled from the oil cup,
The oil sump portion has an annular groove for accumulating the oil, and is integrally provided on the upper surface of the support portion.

Preferably, the width of the annular groove is smaller than the distance from the tip of the oil sump to the lid.

In the invention according to claim 1, the oil cup forming a part of the damper mechanism is integrally provided on the upper surface portion of the support portion. That is, an oil cup is integrally provided in the support portion that supports the rotor, and a part of the support portion also serves as a damper mechanism. The number of parts can be reduced as compared with the case where the support portion and the oil cup are separately configured. Therefore, it is possible to manufacture the eddy current instrument while suppressing the cost.

As described above, when the oil cup is integrally provided on the support portion, the damper mechanism can be arranged near the rotor. Compared with the case where the damper mechanism is provided in the vicinity of the pointer side bearing of the second rotary shaft, the following effects are achieved.

Since the damper mechanism is arranged near the rotor, it is possible to more effectively suppress the vibration of the rotor that occurs during rotation. Further, the damper mechanism is arranged farther from the bearing on the pointer side, and it is possible to suppress the oil of the damper mechanism from reaching the lid of the eddy current instrument through the second rotation shaft.

In the invention according to claim 2, the oil cup is surrounded by an oil sump portion for accumulating the oil spilled from the oil cup, and the oil sump portion has an annular groove for accumulating the oil and is integrated with the upper surface portion of the support portion. It is provided in. Even when oil spills from the oil cup during rotation of the rotor, oil can be stored in the oil reservoir.

In the invention according to claim 3, the width of the annular groove is smaller than the distance from the tip of the oil reservoir to the lid. That is, the area between the tip of the oil sump and the lid is wider than the annular groove. Therefore, the oil that has accumulated in the annular groove of the oil reservoir is less likely to move between the tip of the oil reservoir and the lid, and tends to remain in the annular groove.

In the invention according to claim 1 , the support portion reinforcing portion extends upward from the upper surface portion of the support portion along the second rotation axis, and the tip portion of the resistance portion is provided so as to surround the support portion reinforcing portion. ing. Further, the width from the resistance portion to the second rotating shaft includes a portion wider than the width from the tip portion of the resistance portion to the support portion reinforcement portion.

That is, the region between the support reinforcement and the second rotation shaft is wider than the region from the resistance portion to the second rotation shaft. Therefore, the oil filled between the tip portion of the resistance portion and the support portion reinforcing portion is less likely to move between the support portion reinforcing portion and the second rotating shaft, and remains in the oil cup. It tends to be in a state.

3 is a side view of an eddy current instrument according to an embodiment of the present invention. FIG. It is sectional drawing of the state which looked at the eddy current type meter shown in FIG. 1 from the left side. It is a principal part enlarged view of the eddy current type meter shown in FIG. It is a figure explaining the effect|action of the eddy current type meter shown by FIG.

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the description, left and right refer to left and right with respect to the occupant of the motorcycle, and front and rear refer to front and rear with respect to the traveling direction of the motorcycle. Further, in the figure, Fr indicates the front, Rr indicates the rear, Up indicates the upper side, and Dn indicates the lower side.

Please refer to FIG. FIG. 1 shows an instrument body 10 (eddy current instrument) 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 the instrument body 10 is mounted on a motorcycle, for example, and is used as a vehicle speedometer. In front of the rotary shaft 45 (second rotary shaft 45) to which the pointer 11 is attached, a totalizer 12 for displaying the total traveled distance is provided. The pointer 11 and the totalizer 12 operate in conjunction with the rotation of the front wheels of the two-wheeled vehicle. Hereinafter, details of the instrument body 10 will be described.

Please refer to FIG. The instrument body 10 includes a bearing body 20, a base portion 30 into which the bearing body 20 is inserted, a lid body 40 that covers the base portion 30, and parts provided on the base portion 30 and the lid body 40.

The bearing body 20 includes a tubular member 21 and a slide bearing 22 made of a sintered metal and provided on the inner circumference of the tubular member 21. A first rotating shaft 23 is rotatably provided on the inner circumference of the plain bearing 22.

The base 30 is, for example, a base plate configured by press forming a general 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 peripheral edge of the tubular member 21. The tubular member 21 and the base 30 are fixed by caulking the ring member 32 after inserting the ring member 32 into the insertion hole 31. The tubular member 21 and the ring member 32 can be integrated to reduce the number of parts.

A cup-shaped magnetic conductor 24 and a donut-shaped magnet 25 are fixed to the upper part 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 is open upward. The magnet 25 is arranged so as to be housed in the magnetic conductor 24 that is open upward. As the magnet 25, for example, a radially magnetized sintered magnet made of alnico (Al—Ni—Co) is used. The upper end of the first rotating shaft 23 is hollowed downward, and the second bearing 26 is arranged in this hollowed 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 shaft 23 and constitutes a part of a gear mechanism 16 that transmits the rotation of the first rotation shaft 23 to the integrator. A well-known technique such as a worm gear is adopted for the gear mechanism 16. Detailed description is omitted.

The lid 40 is, for example, an injection-molded product obtained 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 may be made of polybutylene terephthalate resin (PBT). An accommodating portion 43 for accommodating the integrator 12 is formed in the ceiling portion 42 from approximately the center to the front portion.

A circular support hole 44 is formed on the axis line CL of the first rotating shaft 23 at approximately the center of the ceiling portion 42. That is, the second rotation shaft 45 is arranged on the same axis line CL as the first rotation shaft 23. The second rotation shaft 45 is rotatably supported by the lid 40 in a state of being 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 resin rotor support portion 50 is attached to the second rotating shaft 45. Details of the rotor support portion 50 will be described later. The rotor 60 supported by the rotor support portion 50 is made of a non-magnetic metal such as aluminum and is formed into 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 beard spring 46 that biases the second rotating shaft 45 is provided. The beard spring 46 has a center portion fixed to the second rotating shaft 45 and an end portion hooked on a hook 47 fixed to the ceiling portion 42. The ends are fixed by, for example, heat staking. The beard spring 46 biases the second rotation shaft 45 in a direction opposite to the rotation direction of the rotor 60 due to the eddy current.

Returning to FIG. The lid 40 is provided with left and right integrator support portions 70, 70 (only the left integrator support portion 70 is shown) that supports both ends of the shaft 17 of the integrator 12. Hereinafter, the left side totalizer support 70 will be described. The right-side totalizer support 70 has the same structure as the left-side totalizer support 70. A description of the right side totalizer support 70 is omitted.

The totalizer support portion 70 includes a groove portion 71 that extends in the vertical direction to support the shaft 17, and a fixing portion 72 that fixes the shaft 17 supported by the groove portion 71. The fixed portion 72 includes a restraining portion 73 that restrains the upper end of the shaft 17. The restraining portion 73 extends in the front-rear direction. That is, the suppressing portion 73 and the groove portion 71 are orthogonal to each other.

A boss 74 is welded to the integrator support portion 70 along the direction in which the groove 71 extends. The welded portion of the boss body 74 is formed thinner than other welded portions. The rear end portion 75 of the fixed portion 72 is in contact with the boss body 74.

The totalizer support portion 70 having the above-described configuration has the following effects. The restraining portion 73 of the fixing portion 72 is orthogonal to the groove portion 71 extending in the height direction. Therefore, when positioning the shaft 17, it becomes easy to visually recognize the position of the shaft 17.

Further, the boss body 74 is welded in contact with the rear end portion 75 of the fixed portion 72. Therefore, variations in the welding position of the boss 74 during welding can be suppressed. Furthermore, the welded portion is formed thin, and when a force is applied to the fixing portion 72, the boss body 74 is easily broken. When the integrator 12 is removed and tampered with, the tampered mark of the integrator 12 clearly remains due to the state of the boss body 74, for example, the presence or absence of the boss body 74, the bending of the boss body 74, and the like.

Please refer to FIG. The instrument body 10 has a damper mechanism 19 for suppressing abrupt rotation of the second rotating shaft 45 and the rotor 60. The damper mechanism 19 will be described below.

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

An insert hole 61 for insert-molding the rotor support portion 50 is formed in the center of the rotor 60. An upper edge 62, which is an 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 axis 45, and an upper surface that supports the upper surface side of the rotor 60. And part 55. From the upper surface portion 55, a support portion reinforcing portion 58 extends upward along the second rotating shaft 45.

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

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

In the present embodiment, the edge of the upper surface portion 55 extends upward to form the oil sump portion 56 and the annular groove 56a. However, for example, on the inner peripheral side of the edge of the upper surface portion 55, the upper surface portion is formed. 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 40.

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

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

Returning to FIG. 1 and FIG. When the two-wheeled vehicle runs, the first rotary shaft 23 rotates in conjunction with the rotation of the front wheels, and the magnetic conductor 24 and the magnet 25 fixed to the first rotary shaft 23 rotate integrally. The rotation of the magnet 25 causes an eddy current in the rotor 60, causing the rotor 60 to rotate. The pointer (see FIG. 1) is displaced by the rotation of the rotor 60. As the speed of the motorcycle increases, the rotation speed of the magnet 25 increases and the eddy current generated in the rotor 60 also increases. When the eddy current increases, the rotating force 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 biasing force of the beard 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 integrator 12 via the gear mechanism 16. The number displayed on the totalizer 12 allows the occupant to visually check the traveling distance.

Next, the operation and effect of the present invention will be described.

Please refer to FIG. The oil cup 52 that constitutes a part of the damper mechanism 19 is integrally provided on the upper surface portion 55 of the rotor support portion 50. That is, the rotor support 50 is integrally provided with the oil cup 52, and a part of the rotor support 50 also serves as the damper mechanism 19. The number of parts can be reduced as compared with the case where the rotor support portion 50 and the oil cup 52 are separately configured. Therefore, it is possible to manufacture the eddy current instrument while suppressing the cost.

Similarly, the resistance portion 49 is formed integrally with the lid body 40. That is, both the oil cup 52 and the resistance portion 49 that configure the damper mechanism 19 are integrally formed with the components that configure the instrument body 10. Therefore, the number of parts can be further reduced.

As described above, when the oil cup 52 is integrally provided on the rotor support portion 50, the damper mechanism 19 can be arranged near the rotor 60. Compared with the case where the damper mechanism 19 is provided in the vicinity of the support hole 44 of the second rotating shaft 45, the following effects are achieved.

Since the damper mechanism 19 is arranged in the vicinity of the rotor 60, the vibration of the rotor 60 that occurs during rotation can be suppressed more efficiently. Further, the damper mechanism 19 is arranged farther from the support hole 44, and it is possible to suppress the oil 51 of the damper mechanism 19 from reaching the ceiling portion 42 along the second rotation shaft 45 (see FIG. 2 ). ).

In addition, the oil cup 52 is surrounded by an oil sump portion 56 for accumulating oil spilled from the oil cup 52, and the oil sump portion 56 has an annular groove 56a for accumulating oil, and the upper surface portion 55 of the rotor support portion 50. It is provided integrally with. Even when the oil 51 spills from the oil cup 52 during the rotation of the rotor 60, the oil 51 can be stored in the oil reservoir 56.

In addition, 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 40. That is, the area between the tip of the oil sump 56 and the lid 40 is wider than the annular groove 56a. Therefore, the oil that has accumulated in the annular groove 56a is less likely to move between the tip of the oil reservoir 56 and the lid, and tends to remain in the annular groove 56a.

The support portion reinforcement portion 58 extends upward from the upper surface portion 55 of the rotor support portion 50 along the second rotation shaft 45, and the tip portion 48 of the resistance portion 49 is provided so as to surround the support portion reinforcement portion 58. ing. Further, the width W2 from the resistance portion 49 to the second rotation shaft 45 includes a portion wider than the width W3 from the tip end portion 48 of the resistance portion 49 to the support portion reinforcement portion 58.

That is, the area W3 between the support portion reinforcing portion 58 and the tip portion 48 of the resistance portion 49 is narrower than the area W2 between the resistance portion 49 and the second rotating shaft 45. Therefore, the oil filled between the tip end portion 48 and the support portion reinforcing portion 58 becomes hard to move between the support portion reinforcing portion 58 and the second rotating shaft 45, and is accumulated in the oil cup 52. It tends to be left as it is.

The tip portion 48 of the resistance portion 49 extends to the vicinity of the upper surface portion of the rotor support portion 50. When the rotor 60 rotates, the tip end portion 48 and the upper surface portion 55 can come into contact with each other. Therefore, the movement of the rotor 60 can be restricted in the thrust direction of the second rotating shaft 45.

Please also refer to FIG. The rotor 60 is formed into a cup shape opened downward by press working. Therefore, the rotor 60 tends to deform in the direction of the arrow (1) (the force that tends to return acts). Further, the resin oil cup 52 is internally stressed during molding. Therefore, the oil cup 52 tends to deform in the direction of the arrow (2). → Due to the force acting in the directions of (1) and (2), stress is applied to the boundary portion 59 which is a boundary between the upper surface portion 55 of the rotor support portion 50 and the main body portion 54.

By the way, the upper edge 62, which is the edge on the upper surface side of the insert hole 61, is chamfered. After the insert molding, the upper edge 62 comes into surface contact with the boundary 59 of the rotor support portion 50, so that the force applied to the boundary 59 is dispersed. As a result, the boundary portion 59 is less likely to be loaded.

The eddy current instrument according to the present invention can be mounted not only on a two-wheeled vehicle but also on a vehicle such as a four-wheeled vehicle or a three-wheeled vehicle and other vehicles.

Further, the eddy current meter has been described based on the example adopted in the vehicle speed meter, but it can be applied to a tachometer or the like.

That is, the present invention is not limited to the examples as long as the actions and effects of the present invention are exhibited.

The eddy current instrument of the present invention is suitable for use in a vehicle speedometer.

DESCRIPTION OF SYMBOLS 10... Instrument main body 19... Damper mechanism 23... 1st rotary body 30... Base part 40... Lid body 45... 2nd rotating shaft 48... Tip part 49... Resistor part 50... Rotor support part 52... Oil cup 55... Top surface part 56... Oil sump part 56a... Annular groove 58... Support part reinforcement part 59... Boundary part 60... Rotor 61... Insert hole 62... Upper edge

Claims (3)

A base portion, a first rotation shaft rotatably supported by the base portion, a magnet attached to the first rotation shaft and rotating with the first rotation shaft, and a lid body covering the base portion, A second rotation shaft rotatably attached to the lid, a resin support portion attached to the second rotation shaft, and a rotation caused by an eddy current generated by rotation of the magnet supported by the support portion. Eddy current measuring instrument having a rotor for rotating and a damper mechanism for suppressing abrupt rotation of the second rotating shaft and the rotor,
The damper mechanism includes an oil cup that is filled with oil and is rotatable with the second rotating shaft, and a resistance portion that extends from the lid body to the oil cup and has a tip end immersed in the oil. ,
The oil cup is integrally provided on the upper surface of the support portion ,
A support portion reinforcing portion extends upward from the upper surface portion of the support portion along the second rotation axis;
The tip portion of the resistance portion is provided so as to surround the support portion reinforcing portion,
An eddy current instrument , wherein a width from the resistance portion to the second rotation axis includes a portion wider than a width from a tip end portion of the resistance portion to the support portion reinforcement portion . The oil cup is surrounded by an oil reservoir that stores the oil spilled from the oil cup,
The eddy current instrument according to claim 1, wherein the oil sump portion has an annular groove for accumulating the oil and is integrally provided on an upper surface portion of the support portion. The eddy current meter according to claim 2, wherein the width of the annular groove is smaller than the distance from the tip of the oil reservoir to the lid.

Images