JP6822066B2 - Metal foreign matter detector - Google Patents

Description

The present invention relates to a metal foreign matter detecting device, and more particularly to a metal foreign matter detecting device for detecting metal adhering to the inner peripheral surface of an oil seal.

For example, in a vehicle transmission, an oil seal is attached in advance to an insertion hole formed in a housing, and a shaft such as an input shaft is inserted through the oil seal. This prevents oil from leaking at the shaft insertion portion.

Japanese Unexamined Patent Publication No. 2014-07728

However, if the shaft is inserted with metal foreign matter adhering to the inner peripheral surface of the oil seal, the metal foreign matter enters between the inner peripheral surface of the oil seal and the outer peripheral surface of the shaft, and a gap is created in the oil seal. In some cases. As a result, oil may leak from this gap.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a metal foreign matter detecting device capable of detecting a metallic foreign matter adhering to the inner peripheral surface of an oil seal.

The present invention is provided with a rotating shaft inserted into the oil seal and a proximity sensor provided on the outer peripheral portion of the rotating shaft for detecting metallic foreign matter adhering to the inner peripheral surface of the oil seal. It is a characteristic metal foreign matter detection device.

Further, a plurality of the proximity sensors are arranged in the circumferential direction of the rotation axis.

Further, the proximity sensor includes a first proximity sensor for detecting a foreign substance of iron metal and a second proximity sensor for detecting a foreign substance of non-ferrous metal.

Further, the first proximity sensor and the second proximity sensor are arranged alternately.

Further, the metal foreign matter detecting device further includes a rotating device for rotating the rotating shaft.

Further, the metal foreign matter detecting device further includes an axial moving device for moving the rotating shaft in the axial direction.

According to the metal foreign matter detecting device according to the present invention, it is possible to detect the metallic foreign matter adhering to the inner peripheral surface of the oil seal.

It is a schematic perspective view which shows the application example of the metal foreign matter detection apparatus which concerns on one Embodiment of this invention. It is a vertical sectional view of part A of FIG. It is an enlarged view of the proximity sensor shown in FIG.

Hereinafter, the metal foreign matter detecting device according to the embodiment of the present invention will be described with reference to the accompanying drawings. In the embodiment described later, each direction shown in the figure is merely defined for convenience of explanation.

FIG. 1 is a schematic perspective view showing an application example of the metal foreign matter detecting device 100 according to the embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of a portion shown by a broken line A in FIG.

As shown in FIG. 1, the metal foreign matter detecting device 100 is provided on the rotating shaft 2 inserted into the oil seal 1 and the outer peripheral portion of the rotating shaft 2, and is provided on the inner peripheral surface of the oil seal 1 (non-metal foreign matter). A proximity sensor 3 for detecting (shown) is provided. Further, the metal foreign matter detecting device 100 includes a rotating device 4 for rotating the rotating shaft 2 and an axial moving device 5 for moving the rotating shaft 2 in the axial direction. Reference numeral H indicates a clutch housing for accommodating a clutch (not shown) of a vehicle transmission. However, in FIG. 1, only the inner half of the oil seal 1 and the clutch housing H are shown so that the shape of the metal foreign matter detecting device 100 can be understood.

The clutch housing H is made of a metal material such as cast iron or an aluminum alloy, and is formed in a bowl shape. The clutch housing H of the present embodiment is arranged so that the opening h1 faces vertically downward. Further, although not shown, it is assumed that the clutch housing H is mounted on a transport device such as a wheel conveyor.

A mounting portion h2 for mounting a gear housing (not shown) of a vehicle transmission is formed on the upper end edge of the clutch housing H. Further, an insertion hole h3 is formed at a position at the center of the upper end of the clutch housing H so as to penetrate in the vertical direction. The insertion hole h3 is essentially an insertion hole for rotatably inserting an input shaft (not shown) of the transmission.

The oil seal 1 is attached to the insertion hole h3. That is, the oil seal 1 of the present embodiment is a seal member for preventing oil leakage between the input shaft and the insertion hole h3. However, the oil seal 1 may be used to prevent oil leakage between the shaft and its insertion hole.

As shown in FIG. 2, the oil seal 1 is formed in an annular shape, and is fitted and fixed to a step portion s formed in the middle of the insertion hole h3. Specifically, the oil seal 1 includes a rubber seal body 10 having a U-shaped cross section and a lip portion 10a on the inner peripheral surface, and a metal reinforcing ring 11 attached to the seal body 10. , Have. A wedge-shaped lip tip portion 10b is formed on the inner peripheral surface portion of the lip portion 10a. Reference numeral 12 indicates an annular coil spring for pressing the lip tip portion 10b against the outer peripheral surface of the input shaft.

The rotating shaft 2 is composed of a cylindrical or cylindrical member and is arranged in the vertical direction. Specifically, the rotating shaft 2 is connected to a rotating device 4 and an axial moving device 5 (see FIG. 1), which will be described later, and is arranged so as to extend vertically upward from each of the devices 4 and 5. To.

Further, as will be described in detail later, a plurality of proximity sensors 3 are arranged in the circumferential direction on the outer peripheral portion of the rotating shaft 2. The rotating shaft 2 and each proximity sensor 3 are provided so that a gap of a certain distance (for example, 1 mm to 2 mm) is formed between the outer peripheral surface of each proximity sensor 3 and the lip tip portion 10b of the oil seal 1.

FIG. 3 is an enlarged view of a portion of the proximity sensor 3 shown in FIG. As shown in FIG. 3, a plurality of proximity sensors 3 are arranged in the circumferential direction of the rotation shaft 2. Specifically, the proximity sensor 3 includes a first proximity sensor 3a for detecting an iron metal foreign substance (not shown) and a second proximity sensor 3b for detecting a non-ferrous metal foreign substance (not shown), and the rotating shaft 2 It is arranged alternately on the outer periphery of the.

In the present embodiment, the iron-metal foreign matter is made of cast iron, and the non-ferrous metal foreign matter is made of aluminum alloy. However, the iron metal foreign substance may be an iron metal foreign substance other than cast iron, and the non-ferrous metal foreign substance may be a non-ferrous metal foreign substance other than an aluminum alloy.

Further, the metal foreign matter is mainly a fine metal piece generated in the machining process of a component of a transmission, for example, linear shavings. However, the metal foreign matter may be something other than this.

In the present embodiment, nine first proximity sensors 3a and nine second proximity sensors 3b are provided. Further, the proximity sensors 3a and 3b are alternately arranged on the outer peripheral surface of the upper end of the rotating shaft 2 at equal intervals in the circumferential direction. However, the arrangement and number of the proximity sensors 3a and 3b are arbitrary.

Each of the proximity sensors 3a and 3b described above comprises an inductive square sensor. More specifically, the proximity sensors 3a and 3b include a case 30 connected to the outer peripheral surface of the upper end of the rotating shaft 2, a detection unit (not shown) and a circuit board (not shown) housed in the case 30, and a circuit board. With a cord 31 connected to.

The case 30 is a rectangular parallelepiped case made of a metal material or a resin material, and is arranged so as to extend in the vertical direction. Although not shown, the case 30 is screwed and fixed to the outer peripheral surface of the rotating shaft 2. However, the case 30 is not limited to a rectangular parallelepiped shape, and may be, for example, a cylindrical shape. Further, the case 30 may be fixed to the rotating shaft 2 by a method such as welding instead of screwing.

The detection unit has an electromagnetic coil arranged at the upper end portion in the case 30. The circuit board is formed by mounting electronic components constituting a transmission circuit and the like, and is electrically connected to an electromagnetic coil. The cord 31 extends downward from the lower end position of each case 30, is bundled together, and is connected to a controller (not shown) as an electronic control device.

As shown in FIG. 1, the rotating device 4 has a first rotary air cylinder (not shown) as a means for rotating the rotating shaft 2. Although not shown, the first rotary air cylinder is provided between, for example, a pair of air cylinders, that is, a forward rotation air cylinder and a reverse rotation air cylinder, and a first air cylinder and a compressed air supply source (for example, a compressor). It is equipped with a solenoid valve. The first solenoid valve is electrically connected to the controller and is automatically controlled by the controller. When the first electromagnetic valve is switched to the normal rotation position by the controller, compressed air is supplied to the forward rotation air cylinder, compressed air is discharged from the reverse rotation air cylinder, and the rotation shaft 2 is in the forward rotation direction (clockwise) indicated by the arrow B1. It is rotated by a predetermined angle (90 ° in this embodiment). Conversely, when the first solenoid valve is switched to the reverse position by the controller, compressed air is supplied to the reverse rotation air cylinder, compressed air is discharged from the forward rotation air cylinder, and the rotating shaft 2 is in the reverse direction indicated by the arrow B2. It is rotated by a predetermined angle (90 ° in this embodiment) in a counterclockwise direction. When the first solenoid valve is switched to the stop position by the controller, compressed air is not supplied to either the forward rotation air cylinder or the reverse rotation air cylinder, and the rotary shaft 2 is in the drive stop state. The rotation angle of the rotation shaft 2 is arbitrary, and may be an angle other than 90 °.

On the other hand, the axial moving device 5 has a second rotary air cylinder (not shown) as a means for moving the rotating shaft 2 in the axial direction. Although not shown, the second rotary air cylinder is provided between, for example, a pair of air cylinders, that is, an ascending air cylinder and a descending air cylinder, and a second air cylinder and a compressed air supply source (for example, a compressor). It is equipped with a solenoid valve. The second solenoid valve is electrically connected to the controller and is automatically controlled by the controller. When the second solenoid valve is switched to the ascending position by the controller, compressed air is supplied to the ascending air cylinder, compressed air is discharged from the descending air cylinder, and the rotating shaft 2 is raised to the uppermost position. On the contrary, when the second solenoid valve is switched to the lowering position by the controller, compressed air is supplied to the lowering air cylinder, compressed air is discharged from the ascending air cylinder, and the rotating shaft 2 is lowered to the lowermost position. .. When the second solenoid valve is switched to the stop position by the controller, compressed air is not supplied to either the ascending air cylinder or the descending air cylinder, and the rotary shaft 2 is in the drive stop state.

In the axial movement device 5, when the rotating shaft 2 is located at the uppermost end, the detection unit of the proximity sensor 3 is arranged so as to be at the same height position as the oil seal 1. Further, although not shown, when the rotating shaft 2 is located at the lowermost end, the upper end portion of the rotating shaft 2 comes out of the insertion hole h3 and is arranged directly below the insertion hole h3.

The rotating device 4 and the axial moving device 5 may use other means, for example, a servomotor, instead of the rotary air cylinder, as means for rotating and raising and lowering the rotating shaft 2. The servomotor is electrically connected to the controller and is automatically controlled by the controller.

Next, the operation and effect of the metal foreign matter detecting device 100 according to the present embodiment will be described. First, a procedure for detecting a metallic foreign substance by the metallic foreign matter detecting device 100 will be described. It is assumed that the oil seal 1 is already attached to the insertion hole h3 of the clutch housing H. Further, in the detection unit of the first proximity sensor 3a and the second proximity sensor 3b, it is assumed that a current flows from the circuit board to the electromagnetic coil to generate a magnetic field.

First, the clutch housing H is conveyed while being mounted on a transfer device (not shown), and is stopped at a position where the oil seal 1 and the rotating shaft 2 are coaxial.

Next, the controller raises the rotary shaft 2 by executing control for switching the second solenoid valve of the axial movement device 5 to the raising position. As a result, the rotating shaft 2 is inserted into the insertion hole h3 from the lower end thereof, and stops when the detection unit of the proximity sensor 3 is at the same height position as the oil seal 1.

In this state, the controller rotates the rotating shaft 2 by 90 ° in the normal rotation direction indicated by the arrow B1 by executing the control of switching the first solenoid valve of the rotating device 4 to the normal rotation position. Subsequently, the controller executes control to switch the first solenoid valve of the rotating device 4 to the reversing position, thereby rotating the rotating shaft 2 by 90 ° in the reversing direction indicated by the arrow B2 and returning it to the original position. Note that this reciprocating rotation operation may be repeated.

During this reciprocating rotation operation, if iron metal or non-ferrous metal foreign matter does not adhere to the surface of the lip portion 10a of the oil seal 1, the first proximity sensor 3a and the second proximity sensor 3b do not detect these metallic foreign matter.

On the other hand, for example, if iron metal foreign matter is attached to the surface of the lip portion 10a, the first proximity sensor 3a at a position facing the adhered portion can detect the iron metal foreign matter. Further, if a non-ferrous metal foreign substance is attached to the surface of the lip portion 10a, the second proximity sensor 3b at a position facing the adhered portion can detect the non-ferrous metal foreign substance. The result of the detection is transmitted to the worker in the field, for example, by displaying it on the display by the controller.

Then, when this detection is completed, the controller lowers the rotary shaft 2 and returns it to the original position by executing the control of switching the second solenoid valve of the axial movement device 5 to the lower position.

Here, as a comparative example, a case where the input shaft is inserted through the oil seal 1 and attached without using the metal foreign matter detecting device 100 will be examined. Here, for example, it is assumed that a linear iron-metal foreign substance made of cast iron or a linear non-ferrous metal foreign substance made of an aluminum alloy is attached to the lip tip portion 10b of the lip portion 10a.

In this case, when the input shaft is inserted vertically downward into the oil seal 1, the above metal foreign matter is sandwiched between the lip tip portion 10b and the input shaft and remains, and the input shaft and the lip tip portion 10b There may be a gap between the two. This gap may occur even if the metal foreign matter has a minute size (for example, a linear foreign matter having a diameter of about 0.2 mm).

However, it is very difficult to visually confirm the adhesion of such metallic foreign matter. Therefore, when the input shaft is inserted into the oil seal 1 in this adhered state, and then the gear housing is attached to the clutch housing H and the gear housing is filled with oil, the oil in the gear housing is filled through this gap. May leak out.

With the metal foreign matter detecting device 100 according to the present embodiment, the metal foreign matter adhering to the lip portion 10a can be easily and surely detected by the first proximity sensor 3a or the second proximity sensor 3b. Then, by removing the detected metallic foreign matter from the lip portion 10a, the above-mentioned oil leakage can be prevented.

In particular, in the present embodiment, by providing the two types of proximity sensors 3 of the first proximity sensor 3a and the second proximity sensor 3b, it is possible to detect any of the above two types of metallic foreign matter.

Further, in the present embodiment, a plurality of the first proximity sensor 3a and the second proximity sensor 3b are arranged on the outer peripheral portion of the rotating shaft 2. Therefore, for example, even if one first proximity sensor 3a cannot detect the iron-metal foreign matter, there is a possibility that the other first proximity sensor 3a can detect the iron-metal foreign matter. Therefore, the detection accuracy of the metallic foreign matter can be improved as compared with the case where the first proximity sensor 3a and the second proximity sensor 3b are arranged one by one.

In particular, in the present embodiment, a plurality of (for example, nine) first proximity sensors 3a and a plurality of (for example, nine) second proximity sensors 3b are alternately arranged at equal intervals in the circumferential direction of the rotation shaft 2. Be placed. According to this configuration, for example, by rotating the rotation axis by 90 °, two or three different first proximity sensors 3a and two or three different second proximity sensors 3b are located at the same position on the lip portion 10a. Will pass through. Therefore, for example, it is possible to accurately detect the above two types of metallic foreign substances simply by rotating the rotating shaft 2 by 1/4. Further, since the rotation angle of the rotation shaft 2 can be reduced, the rotation device 4 can be miniaturized. However, the first proximity sensor 3a and the second proximity sensor 3b may be installed so as to exist at least one in the rotation angle.

Further, in the present embodiment, the axial movement device 5 can move the proximity sensor 3 to the height position of the oil seal 1, and the rotation device 4 can rotate the rotation shaft 2. Therefore, since these operations can be automated, the burden on the operator can be reduced.

In particular, according to the rotating device 4, since the rotating shaft 2 can be slowly rotated at a constant speed, the detection accuracy can be improved as compared with manually rotating the rotating shaft 2.

The present invention is not limited to the above-described embodiment, and can be appropriately modified and implemented without departing from the spirit of the present invention.

For example, although not shown, the above embodiments can be modified as follows. In the following description, detailed description of the same components as those in the above-mentioned basic embodiment will be omitted.

(First modification)
Although not shown, the proximity sensor 3 may be only one of the first proximity sensor 3a and the second proximity sensor 3b. Further, the proximity sensor 3 includes a proximity sensor (for example, a third proximity sensor) for detecting an iron metal foreign substance other than cast iron and a proximity sensor (for example, a fourth proximity sensor) for detecting a non-ferrous metal foreign substance other than an aluminum alloy. You can go out. Further, each proximity sensor 3 is not limited to the inductive sensor having a coil, and may be a capacitance type sensor or a magnetic sensor depending on the type of metal foreign matter.

As described above, in the first modification, the type of the proximity sensor 3 can be deleted, added, or changed according to the use of the oil seal 1 and the type of the metal foreign matter to be attached.

(Second modification)
In the above embodiment, the cord 31 of the proximity sensor 3 extends downward from the lower end position of each case 30 and is bundled into one and connected to the controller. Although not shown, in the second modification, each cord 31 may be configured to pass through, for example, the inside of the rotating shaft 2. Specifically, each cord 31 may be inserted into the inside of the rotating shaft 2 formed in a cylindrical shape, and may be connected to the controller through the inside of the rotating shaft 2. As a result, the exposure of the cord 31 can be suppressed, so that work efficiency and safety can be improved.

(Third modification example)
Although not shown, the rotating shaft 2 may be arranged in any direction according to the direction of the oil seal 1 instead of the vertical direction. For example, when the metal foreign matter detecting device 100 detects a metallic foreign matter, if the oil seal 1 is oriented in the horizontal direction, the rotating shaft 2 is also arranged in the horizontal direction.

Further, in this third modification, the moving direction of the axial moving device 5 is changed according to the direction of the rotating shaft 2.

(Fourth modification)
The metal foreign matter detecting device 100 does not have to include at least one of the rotating device 4 and the axial moving device 5. That is, it is also possible for the operator to grasp the rotating shaft 2 and insert the rotating shaft 2 through the oil seal 1. It is also possible for the operator to grasp the rotating shaft 2 and rotate the rotating shaft 2. As described above, by omitting at least one of the rotating device 4 and the axial moving device 5, the manufacturing cost can be reduced.

1 Oil seal 2 Rotating shaft 3 Proximity sensor 4 Rotating device 5 Axial moving device 100 Metal foreign matter detection device

Claims (5)

The rotating shaft inserted into the oil seal and
A proximity sensor provided on the outer peripheral portion of the rotating shaft and for detecting metal foreign matter adhering to the inner peripheral surface of the oil seal is provided .
The proximity sensor is a metal foreign matter detecting device including a first proximity sensor for detecting an iron-metal foreign matter and a second proximity sensor for detecting a non-ferrous metal foreign matter . The metal foreign matter detecting device according to claim 1, wherein the first proximity sensor and the second proximity sensor are arranged alternately . The rotating shaft inserted into the oil seal and
A proximity sensor provided on the outer peripheral portion of the rotating shaft for detecting metallic foreign matter adhering to the inner peripheral surface of the oil seal, and
Metallic foreign matter detection device being characterized in that and a rotating device for rotating the rotary shaft. The rotating shaft inserted into the oil seal and
A proximity sensor provided on the outer peripheral portion of the rotating shaft for detecting metallic foreign matter adhering to the inner peripheral surface of the oil seal, and
Metal foreign object detection apparatus characterized by comprising a an axial movement device for moving the rotary shaft in the axial direction. The metal foreign matter detecting device according to any one of claims 1 to 4 , wherein a plurality of the proximity sensors are arranged in the circumferential direction of the rotation axis .

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