JPH03253452A - Rotation speed detecting device - Google Patents

Abstract

PURPOSE:To stabilize performance of ABS and so on by holding the distance between a sensor rotor and a rotation speed detection sensor at an optimum value through bringing the outer circumferential surface of a roller into contact with the outer circumferential surface of the sensor rotor so as to securely detect rotation speed of a body of rotation to which wheels and so on are fixed. CONSTITUTION:A holder 20 holding a rotation speed detection sensor 15 is elastically pressed toward the outer circumferential surface of a sensor rotor 12 by elasticity of a compression spring 26, and rollers 25 and 25 supported by arm pieces 21 and 21 fixed to the holder 20 are brought into contact with the outer circumferential surface of the sensor rotor 12. Thus, the distance 1 between an end surface 15a of the rotation speed detection sensor 15 and the outer circumferential surface of the sensor rotor 12 is kept constant all the time despite a manufacturing error of a housing corresponding member 14, a body of rotation 13 or the sensor rotor 12 or elastic deformation and so on of theses parts. Therefore, rotation speed of a wheel and so on supported by an end part of the body of rotation 13 can be securely detected in a stable state all the time.

Description

[Detailed Description of the Invention] (Industrial Application Field) The rotational speed detection device according to the present invention is incorporated into an anti-skid brake system for automobiles (hereinafter referred to as rABSJ in Hayabusa), Detects the rotational speed of the wheels and prevents them from locking during braking (wheels not rotating even though the car is running), or detects the rotational speed of each axle built into an automatic transmission. It is used to detect the rotational speed of the shaft and determine the timing for locking up the shafts (mechanically coupling the shafts to each other).

(Prior Art) In various mechanical devices, the rotational speed of a shaft has been detected. For example, in ABS, for example, Japanese Patent Publication No. 52-46331, Japanese Patent Application Laid-open No. 62 -2
A rotational speed detection device such as that disclosed in Japanese Patent No. 49069 is used to detect the rotational speed of a wheel during braking.

Among these, the rotational speed detection device disclosed in Japanese Patent Publication No. 52-46331 is constructed as shown in FIG.

In this Fig. 5, reference numeral 1 denotes a hub having a flange 2 fixed on its outer circumferential surface for fixing a wheel, and an outer raceway 3.3 is formed on the outer circumferential surface of this hub 1, which is a rotating body. ing. 4
5.5 is a rolling element, which includes an outer raceway 3.3 formed on the outer peripheral surface of the hub 1 and an inner raceway 6.6 formed on the inner peripheral surface of the outer ring 4. The hub 1 is mounted between the outer ring 4 and the outer ring 4 so that the hub 1 can freely rotate inside the outer ring 4.

A gear-shaped sensor rotor is fixed to one end of the hub 1, and a part of the cover 9 fixed to the end of the outer ring 4,
A rotational speed detection sensor 8 is provided at a portion facing the sensor rotor 7 to freely detect the rotational speed of the hub 1 to which the sensor rotor 7 is fixed.

Further, in the case of the rotational speed detection device disclosed in Japanese Patent Application Laid-Open No. 62-249069, as shown in FIG. The end of the rotational speed detection sensor 8 provided at the same position is opposed to the outer peripheral edge of the sensor rotor 7.

In these conventionally known rotational speed detection devices,
As the sensor rotor rotates together with the hub 1,
The output voltage of the rotational speed detection sensor 8 provided opposite to the sensor rotor 7 changes.

In this way, the frequency at which the output voltage of the rotational speed detection sensor 8 changes as the sensor rotor 7 fixed to the hub 1 rotates is proportional to the rotational speed of the hub 1.
If the output signal of the rotational speed detection sensor 8 is input to a controller (not shown), the rotational speed of the wheel fixed to the hub 1 (
rotation speed).

Further, as shown in FIG. 7, a sensor rotor 12 is formed by forming a large number of through holes 11, 11 at equal intervals in a short cylindrical main body 10.
A housing-equivalent member 1 such as an outer ring, which is externally fitted and fixed to the outer peripheral surface of the rotating body 13 and surrounds the rotating body 13.
4, a rotation speed detection sensor 15, and the sensor rotor 12
A rotational speed detection device that is provided in a state where it is opposed to the rotation speed detection device has also been considered in the past.

(Issue m to be solved by the invention) However, in the case of the conventional rotational speed detection device as described above,
This causes the following inconvenience.

That is, in the case of the conventional rotational speed detection device, the sensor rotor 7
．． 12 to a rotating body such as the hub 1, and a rotation speed detection sensor 8.
were fixed to fixed side members such as the outer ring 4, and the sensor rotor 7.12 and the rotational speed detection sensor 8.15 were opposed to each other at a predetermined distance, so in some cases, rotation may occur. There may be cases where the output voltage of the speed detection sensor 8.15 is not constant.

This is because the voltage of the output signal sent from the rotational speed detection sensor 8.15 is the same as that of the rotational speed detection sensor 8.1.
5 and the sensor rotor 7.12, this distance varies greatly depending on the distance between the hub 1, the outer ring 4, etc.
Subtle deviations may occur due to manufacturing errors in each member on the fixed side and also in the sensor rotor 7.12. In addition, each of the above members 1
．． Even if manufacturing errors such as 4.7 are negligible, stress applied to each member on the rotating side and fixed side, such as the parfait and outer ring 4, as the car is driven, causes the errors in each member 1.4.
13.14 is elastically distorted, the distance between the rotation speed detection sensor 8.15 and the sensor rotor 7.12 is
-It changes over time.

Changes in the above distance are small, rotation speed detection sensor 8.15
If the voltage of the output signal sent from the
The absolute value of the voltage of the output signal is insufficient, and the controller becomes unable to detect the rotational speed of the wheel, even if only temporarily.

The rotational speed detection device of the present invention eliminates the above-mentioned disadvantages.

(Means for Solving the Problems) The rotational speed detection device of the present invention, like the conventional rotational speed detection device described above, includes a sensor rotor fixed to the outer peripheral surface of a rotating body, and a sensor rotor fixed to the outer peripheral surface of the rotating body. The sensor rotor is provided in a member corresponding to a surrounding housing and includes a rotation speed detection sensor facing the sensor rotor.

Furthermore, in the rotational speed detection device of the present invention, the rotational speed detection sensor is elastically supported by the member corresponding to the housing, so that the rotational speed detection sensor is directed toward the circumferential surface of the sensor rotor. It is pressed elastically.

At the same time, a roller is rotatably supported on a pivot shaft fixed to the rotational speed detection sensor in parallel with the rotating body, and the outer circumferential surface of the roller is brought into contact with the outer circumferential surface of the sensor rotor or the rotating body. The distance between the sensor rotor and the rotational speed detection sensor is maintained at an appropriate value.

(Function) When the rotational speed detection device of the present invention configured as described above detects the rotational speed of a wheel, etc. that is rotatably supported by a rolling bearing, the operation itself is similar to that of the conventional rotational speed described above. It is similar to the detection device.

However, in the case of the rotational speed detection device of the present invention, the rotational speed detection sensor is elastically pressed toward the circumferential surface of the sensor rotor, and a roller is rotatably supported on a pivot fixed to the detection sensor. Since the outer circumferential surface of the sensor rotor or the rotating body is brought into contact with the outer circumferential surface c of the sensor rotor, the distance C between the rotational speed detection sensor and the sensor rotor is always maintained constant C, and the wheels, etc. that are rotatably supported by rolling bearings. The rotational speed can always be detected reliably and in a stable state.

(Example) Next, the present invention will be explained in more detail while explaining the illustrated embodiment.

1 to 3 show a first embodiment of the present invention, in which FIG. 1 is a half sectional view, FIG. 2 is a side view of FIG.
FIG. 3 is a partially cutaway side view of the sensor rotor.

Reference numeral 13 denotes a rotating body, and in the case of a rotational speed detection device as shown in FIG. 346, the hub 1 corresponds to this rotating body 13. Reference numeral 14 denotes a member equivalent to a housing, and in the case of a rotational speed detection device as shown in FIG. 346, the outer ring 4 becomes the member equivalent to the housing 14.

A short cylindrical sensor rotor 12 is externally fitted and fixed on the outer peripheral surface of the rotating body 13. This sensor rotor 12 has
As shown in FIG. 3, a plurality of through holes 11.
11 are formed at equal pitches.

A mounting hole 16 is formed in a part of the housing equivalent member 14 that faces the outer circumferential surface of the sensor rotor 12, and a rotation speed detection sensor 15 is mounted inside the hole 16. It is supported via a shaped casing 17.

That is, the casing 1 is made of slippery synthetic resin or the like.
7 has a mounting flange 18 at its base end (upper end in FIG. 1), and this mounting flange 18 is fixed around the mounting hole 16 with screws. In this state, the main body portion 19 of the casing 17 protrudes inside the housing equivalent member 14.

In the main body portion 19 of the casing 17 fixed to a predetermined portion of the housing equivalent member 14 as described above, there is a holder 20 formed into a cylindrical shape by press-forming a metal plate or the like.
is housed so that it can freely move toward and away from the sensor rotor 12.

A rotation speed detection sensor 1 is installed inside the cylindrical holder 20.
5, and @edge ('s1) of this holder 2o.
A pivot shaft 22.22 parallel to the rotating body 13 is provided at the tip of a pair of arm pieces 21.21 extending from the lower edge of the figure.

A plurality of rolling elements 2 are provided around each pivot shaft 22, 22, respectively.
4.24, rollers 25.25 are rotatably supported, and a part of each roller 25.25 (lower end in FIG. 1) is connected to the tip (the first It is made to protrude toward the sensor rotor 12 from the lower end of the figure).

On the other hand, a pair of notches 23.23 are formed at the opening edge of the casing 17 (the lower edge in FIG. By engaging the holder 20 in the casing 17
prevents rotation.

Therefore, regardless of whether the holder 20 moves toward or away from the rotating body 13, the pair of pivot shafts 22, 22 and the rotating body 13 are always maintained in a parallel state.

Therefore, it is pivoted on each axis 22.22, and as described below,
Roller 25.25 in contact with the outer peripheral surface of the sensor rotor 12
rotation can be performed in a stable manner at all times.

Further, a compression spring 26 is provided between the inner surface of the main body portion 19 of the casing 17 and the base end surface of the holder 20 holding the rotational speed detection sensor 15.

For this reason, the roller 25.25 rotatably supported by the pair of pivots 22.22 is elastically attached to the outer peripheral surface of the sensor rotor 12 in a portion away from the through hole 11.11. are in contact.

In the rotational speed detection device of the present invention configured as described above, the operation itself when detecting the rotational speed of the rotating body 13 to which wheels or the like are fixed is similar to that of the conventional rotational speed detection device described above. be.

That is, when the rotating body 13 to which a wheel or the like is fixed rotates, the sensor rotor 12 rotates in synchronization with the wheel or the like, and the plurality of through holes 11. cross the end face of As a result, the output voltage of the rotational speed detection sensor 15 changes regularly, and the rotational speed of the wheels, etc. can be determined from the frequency at which this output voltage changes.

However, in the case of the rotational speed detection device of the present invention, the holder 20 holding the rotational speed detection sensor 15 is elastically pressed toward the outer peripheral surface of the sensor rotor 12 by the elasticity of the compression spring 26, and the holder 20 is Since the roller 25.25 pivotally supported by the fixed arm piece 21.21 is brought into contact with the outer peripheral surface of the sensor rotor 12, the contact between the end surface 15a of the rotational speed detection sensor 15 and the outer peripheral surface of the sensor rotor 12 is The distance @It is
Regardless of manufacturing errors in the housing equivalent member 14, rotating body 13, or sensor rotor 12, elastic deformation of each of these parts 14, 13, 12, etc., it is always kept constant.

Therefore, the rotational speed of the wheels or the like supported at the end of the rotating body 13 can be detected reliably and always in a stable state.

Next, FIG. 4 shows a second embodiment of the present invention.

In the case of this embodiment, the sensor rotor 27 that is externally fitted and fixed to the outer circumferential surface of the rotating body 13 is a sensor rotor 27 that has gear-shaped irregularities formed on the outer circumferential surface.

Along with changing the outer peripheral shape of the sensor rotor 27 in this way, the roller 25 pivoted on a pair of pivots 22 and 22
．． The outer circumferential surface of 25 is brought into direct contact with the outer circumferential surface of the rotating body 13.

The other configurations and operations are the same as in the first embodiment described above.

(Effects of the Invention) Since the rotational speed detection device of the present invention is configured and operates as described above, it is possible to always keep the voltage of the output signal from the rotational speed detection sensor constant, thereby fixing the wheels, etc. By reliably detecting the rotational speed of the rotating body, the performance of ABS etc. can be stabilized.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention;
The figure is a half sectional view, the 'Hz diagram is a side view of Figure 1,
′! Figure J3 is a partially cutaway side view of the sensor rotor, Figure 4 is a partial cross-sectional view of the second embodiment of the present invention, and Figure 5 is a partially cutaway side view of the sensor rotor.
Figures 1 to 7 are cross-sectional views of three examples of conventional rotational speed detection devices. 1: Hub, 2: Flange, 3: Outer raceway, 4: Outer ring, 5
: Rolling element, 6: Inner raceway, 7: Sensor rotor, 8: Rotation speed detection sensor, 9: Cover 10 two bodies, 11: Through hole,
12: Sensor rotor, 13: Rotating body, 14: Housing equivalent member, 15: Rotation speed detection sensor, 15a: t4
Surface, 16: Mounting hole, 17: Casing, 18: Mounting flange, 19: Body part, 20: Holder, 21:
Arm piece, 22: Pivot, 23: Notch, 24: Rolling element, 2
5: roller, 26: compression spring, 27: sensor rotor. 4th wheat flour]

Claims (4)

[Claims] (1) A sensor rotor fixed to the outer circumferential surface of the rotating body, and provided on a member equivalent to a housing surrounding the rotating body,
In a rotational speed detection device comprising the sensor rotor and a rotational speed detection sensor facing the sensor rotor, the rotational speed detection sensor is elastically supported with respect to a member corresponding to the housing, so that the rotational speed detection sensor is connected to the sensor rotor. The roller is elastically pressed toward the circumferential surface of the rotor, and is rotatably supported on a pivot shaft fixed to the rotational speed detection sensor in parallel with the rotating body, and the outer circumferential surface of the roller is pressed against the sensor rotor. A rotation speed detection device that maintains a distance between a sensor rotor and a rotation speed detection sensor at an appropriate value by bringing the sensor rotor into contact with the outer peripheral surface of the sensor. (2) The rotational speed detection device according to claim 1, wherein the outer circumferential surface of the roller is brought into contact with the outer circumferential surface of the rotating body instead of the outer circumferential surface of the sensor rotor. (3) The rotation speed detection sensor is housed in a cylindrical casing fixed to a member equivalent to the housing so as to be movable toward and away from the rotating body, and a compression spring is provided between the casing and the rotation speed detection sensor. Claims 1 and 2
The rotational speed detection device according to any one of the above. (4) A rotational speed detection sensor is held inside a cylindrical holder that is housed inside a casing and can freely move near and far from the sensor rotor, and the tip of an arm that extends from the edge of this holder. According to claim 3, the holder is prevented from rotating within the casing by providing a pivot in the casing and engaging the proximal portion of the arm with a notch formed in the opening edge of the casing. The rotational speed detection device described.