KR20240015963A - Measuring method of groove width of snap ring mounting portion and apparatus therefor - Google Patents

Abstract

The present invention is a device for measuring the groove width of a snap ring assembly. The device includes a measurer installed across the inside of a support, one end of the measurer is inserted into the snap ring groove of the assembly on which the snap ring is mounted, and the other end of the measurer is oriented in the height direction. It is connected to a connection jig that is installed vertically and can move up and down in the vertical direction, and the connection jig is connected to a moving distance measuring sensor. As the measuring member rotates, the connecting jig moves linearly and the moving distance measuring sensor measures the moving distance of the connecting jig. Provides a groove width measuring device of a snap ring assembly that detects.

Description

{Measuring method of groove width of snap ring mounting portion and apparatus therefor}

The present invention relates to a method and measuring device for measuring the groove width of a snap ring assembly.

Generally, a reducer is used instead of a transmission in electric vehicles (EV). The reducer reduces the rotational speed of the EV drive motor and increases torque to transmit power to the wheels. In the case of an internal combustion engine, a transmission is used to efficiently use the engine, but an EV does not need a transmission because it is capable of producing maximum torque from the start. The EV's reducer further increases the torque of the motor, enabling efficient operation.

Figure 5 shows an example of the structure of the assembly 1' at the output shaft portion of the EV reducer. The output shaft assembly 1' includes an output shaft 2', a first ball bearing 10' mounted on the inlet portion of the output shaft 2', and a second ball bearing 20' mounted on the outlet portion. A large-diameter reduction gear 22' is installed adjacent to the second ball bearing 20'.

Figure 6 is a cross-sectional view of the output shaft assembly 1' of Figure 5 cut along the longitudinal direction. A concave snap ring groove 30' is formed on the upper surface of the first ball bearing 10' on the output shaft 2', and the snap ring S is coupled into the snap ring groove 30'. The snap ring (S) prevents the first ball bearing (10') from leaving in the axial direction. The groove width (d), that is, the height, of the snap ring groove (30') is usually in the range of 1.96 mm to 2.16 mm.

To assemble the snap ring (S), you must accurately measure the depth of the groove width and select a snap ring with the appropriate thickness. However, after assembling the snap ring (S), the allowable gap specification between the upper surface of the snap ring (S) and the snap ring groove (30') is 0 ~ 0.04mm, but if the snap ring (S) is selected or assembled incorrectly due to an error in measuring the groove width, the gap allowable range There is a problem that abnormal noise occurs when the reducer rotates outside of the normal range. To solve this problem, precise measurement of the groove width of the snap ring groove of the output shaft is required.

This groove width and clearance tolerance specifications are adjustable and can be implemented in various modifications within the scope of the patent claims, detailed description of the invention, and attached drawings, and this also falls within the scope of the present invention.

As a related patent document, Patent No. 10-1104933 discloses a device for measuring the clearance of the worm shaft bearing of an automobile's electric power steering using a micrometer unit that measures depth by moving linearly in the longitudinal direction.

Another patent No. 10-1610633 is a drive shaft snap ring groove processing system, in the snap ring groove depth measurement sensor 60' as shown in FIG. 7, a moving sensing unit ( While the movement sensing unit 62' is moving in the direction in which the drive shaft is located along the sensor movement guide 64' that guides the movement of 62'), the probe unit 63' at the head of the moving direction moves the drive shaft. When in contact with the probe unit 63', the rod of the probe unit 63' enters the inside of the movement sensing unit 62', and the movement sensing unit 62' detects the inflow.

The present invention was developed to measure the groove width of the snap ring assembly using a further improved method from a different viewpoint than these patents.

Therefore, the purpose of the present invention is to provide a method and measuring device for measuring the groove width of a snap ring assembly that can accurately and quickly directly measure the groove width of the snap ring groove of the snap ring assembly without error.

In order to achieve the above-described object, the present invention is a device for measuring the groove width of a snap ring assembly. The device includes a measurer installed across the inside of a support, and one end of the measurer is inserted into the snap ring groove of the assembly on which the snap ring is mounted. , the other end of the measuring device is installed vertically along the height direction and is connected to a connection jig that can move up and down in the vertical direction. The connecting jig is connected to a moving distance measurement sensor. As the measuring device rotates, the connecting jig moves linearly to measure the moving distance. Provided is a groove width measuring device of a snap ring assembly in which a measuring sensor detects the moving distance of the connecting jig.

The measuring member includes a central long rod, a measuring boss formed at an end facing the assembly, and a half-moon shaped rotor formed on the outer surface forming a ring of the measuring boss, and the rotor has an upper plane and a lower circular arc. It may include a curved portion of some shape.

When viewed from the side, the outer circumference of the measuring boss and the outer circumference of the curved part of the rotor coincide with each other, so that the curved part of the rotor does not protrude or go inward from the outer circumference of the measuring boss, and the left and right end points of the plane of the rotor are measured. It is the same as the outer peripheral point of the boss, so the plane can form a chord.

The height of the rotor must be smaller than the groove width of the snap ring groove.

In the origin alignment state, the lowest point of the lower surface of the rotor is in contact with the lower surface of the snap ring groove, the plane is aligned parallel to the upper surface of the snap ring groove, and when the probe rotates in one direction, the end of the rotor's plane is in contact with the bottom surface of the snap ring groove. It can rotate to a position where it touches the upper surface and can no longer rotate.

A second rotor having the same structure as the end facing the assembly is formed on the opposite side of the side facing the assembly of the probe, and the second rotor rotates as the probe rotates, allowing the connecting jig to move vertically.

The assembly is an assembly of the output shaft portion of the EV reducer, and the snap ring groove may be formed adjacent to the bearing of the assembly.

The groove width of the snap ring can be the sum of the height of the rotor and the moving distance of the connecting jig.

In addition, the present invention is a method of measuring the groove width using a groove width measuring device of a snap ring assembly, the method comprising: seating an assembly including a first bearing and a snap ring groove adjacent to the first bearing on a base; maintaining the vertical state of the assembly by lowering the fixing jig of the groove width measuring device of the snap ring assembly to press the upper surface of the first bearing of the assembly; Advance the measuring instrument toward the assembly and enter the inside of the snap ring groove along the upper surface of the first bearing, then set the origin so that the lowest point on the lower surface of the rotor is in contact with the lower surface of the snap ring groove, and the plane is parallel to the upper surface of the snap ring groove. A step of achieving alignment; Rotating the measuring device to a position where the upper surface of the rotor comes into contact with the upper surface of the snap ring groove and does not rotate anymore; Detecting the vertical movement distance of the connection jig raised by the rotation of the rotor on the other side of the measuring instrument with a movement distance measurement sensor; and adding the preset height of the rotor and the moving distance measured by the moving distance measuring sensor and determining this as the groove width of the snap ring groove.

The moving distance measurement sensor may be an LVDT (Linear Variable Displacement Transducer) sensor, and any sensor that can additionally measure the moving distance can be applied.

According to the present invention, the groove width of the snap ring groove of the snap ring assembly can be measured directly, accurately and quickly without error, and thus has the effect of solving the problem of noise and vibration caused by the gap in the snap ring of the output shaft of the EV reducer.

1 is a view showing that the groove width measuring device of the snap ring assembly of the present invention measures the groove width, that is, the height, of the snap ring groove of the assembly at the output shaft portion of the EV reducer;
Figure 2 is a perspective view showing the measuring device of the present invention;
Figure 3 is a diagram for explaining the principle of groove width measurement using the groove width measurement device of the present invention;
Figure 4 is a diagram for explaining a groove width measuring method using a groove width measuring device of a snap ring assembly of the present invention, showing each step of the groove width measuring method and the configuration of the groove width measuring device related to each step;
Figure 5 is a diagram showing an example of the assembly structure of the output shaft portion of the EV reducer;
Figure 6 is a cross-sectional view of the output shaft assembly of Figure 5 cut along the longitudinal direction; and
Figure 7 is a diagram showing a snap ring groove depth measurement sensor of a prior patent.

The purpose and effects of the present invention, and technical configurations for achieving them, will become clear by referring to the embodiments described in detail below along with the accompanying drawings. In describing the present invention, if it is determined that a detailed description of a known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

Throughout the specification, when a part is said to “include” a certain element, this means that it may further include other elements rather than excluding other elements, unless specifically stated to the contrary. Meanwhile, in an embodiment of the present invention, each component, functional block, or means may be composed of one or more lower components.

Figure 1 is a diagram showing the groove width measuring device 1 of the snap ring assembly of the present invention measuring the groove width d, that is, the height, of the snap ring groove 30 of the assembly 10 at the output shaft portion of the EV reducer.

The groove width measuring device (1; hereinafter, “groove width measuring device”) of the snap ring assembly of the present invention includes a body (2), a fixture (6) installed on one side of the body (2), and a body (2) installed on the lower part of the body (2). It includes a support (4) integrally connected with (2).

A base 200 for seating the product is installed at a certain interval in the lower part opposite to the fixing jig 6. On the upper surface of the base 200, the output shaft assembly 10 of the EV reducer, which has a snap ring groove 30 for assembling the snap ring S, is formed on the outer surface and is seated vertically. The pressing portion 60 formed in the lower part of the fixing jig 6 presses the upper surface of the assembly 10 and at least the upper surface of the first bearing B1 to stably and reliably maintain the vertical state of the assembly 10.

A slide groove 40 penetrating across the support 4 is formed in the central portion of the support 4. A probe 50, which is a feature of the present invention, is inserted into the groove of the slide 40. One end of the probe 50 is inserted into the snap ring groove 30 toward the output shaft assembly 10, and the other end extends beyond the slide groove 40 to the outside of the support 4. The other end of the measuring device 50 is connected to the connection jig 70. The connection jig 70 is installed vertically along the height direction and can move up and down in the vertical direction. The upper end of the connection jig (70) is connected to the moving distance measurement sensor (80). The moving distance measuring sensor 80 is not particularly limited, but for example, a Linear Variable Displacement Transducer (LVDT) sensor is preferred. LVDT is an electromechanical device that converts mechanical motion or vibration, especially linear motion, into variable current, voltage or electrical signals and vice versa.

Figure 2 is a perspective view showing the measuring device 50 of the present invention. The measuring probe 50 consists of a long hollow rod 52 with an empty center. At one end of the rod 52, that is, at the end facing the output shaft assembly 1, a ring-shaped measuring boss 54 with a larger diameter than the rod 52 is formed. On the outer surface 540 forming the ring of the measurement boss 54, a rotor 56, which is a half-moon (arch) shaped fixture, is formed to protrude outward.

The rotor 56 includes a flat surface 560 at the top and a curved portion 562 that is partially shaped like an arc at the bottom. The plane 560 extends linearly left and right at a predetermined distance outside the empty cavity of the measurement boss 54. The curved portion 562 has an arc shape connecting both ends of the plane 560. When viewed from the left side, it is preferable that the outer circumference 542 of the measurement boss 54 and the outer circumference of the curved portion 562 of the rotor 56 coincide with each other. That is, the curved portion 562 of the rotor 56 is preferably a part of a circle having the same radius of curvature as the measurement boss 54 so that it does not protrude further from or go inward from the outer circumference of the measurement boss 54. Therefore, the left and right end points of the plane 560 are identical to the outer peripheral points of the measurement boss 54, and the plane 560 can be said to provide a kind of chord (a straight line connecting two points on the circumference). .

The configuration of the measurement boss 54 and the rotor 56 described above is formed in the same way at the opposite end of the rod 52, and only the member numbers are different for these and a detailed description is omitted. The measuring boss 54 functions as a guide for inserting the rotor 56 into the snap ring groove 30. Therefore, it is not necessary to form a measurement boss at the opposite end.

In the present invention, the height D of the rotor 56 is defined as the distance between the lowest point of the curved portion 562 and the plane 560 extending vertically upward from the lowest point. The height D of the rotor 56 may be set to be smaller than the groove width d applicable to the snap ring groove 30, for example, 1.6 mm. The measuring probe 50 can be rotated in one direction or the other direction by a rotation drive mechanism (not shown). The measuring probe 50 rotates about the central axis in the longitudinal direction and maintains a state in which it does not move in the axial or radial direction.

Next, the principle of groove width measurement using the groove width measurement device 1 of the present invention will be described with reference to FIG. 3.

As shown in the enlarged view on the left of FIG. 3, the rotor 56 is inserted and accommodated into the snap ring groove 30 in the initial state of the groove width measurement operation (FIG. 3(a)). Since the height D of the rotor 56 is smaller than the groove width d, the front end of the rotor 56 can be accommodated by deeply entering the inner surface of the snap ring groove 30 (outer surface of the output shaft). The lowest point of the lower surface of the rotor 56 is in contact with the lower surface 30a of the snap ring groove 30, and the plane 560 is aligned parallel to the upper surface 30b of the snap ring groove 30. At this time, in the initial state, at the opposite end of the probe 50, the flat surface 560a of the rotor 56a is maintained in complete contact with the flat lower surface 700 of the connection jig 70 without a gap (Figure 3(c) )).

When the probe 50 rotates in the direction of the arrow (FIG. 3(b)) by driving a rotational drive mechanism not shown here, the rotor 56 rotates in the same direction so that the end of the plane 560 becomes the upper surface 30b. ) and rotates to the position (P) where it can no longer rotate. At this time, at the same time, at the opposite end of the probe 50, the end of the flat surface 560a of the rotor 56a gradually pushes up the lower surface 700 of the connecting jig 70, and the connecting jig 70 becomes flat (560). The end of comes into contact with the upper surface 30b and rises to its maximum at a position where it can no longer rotate (Figure 3(d)). The rising distance of the connection jig 70 from the initial to the maximum rising position is detected by the moving distance measurement sensor 80. The rising distance of the connecting jig 70 is equal to the distance D1 between the plane 560 and the upper surface 30b of the rotor 56 in FIG. 3(a). The total height of the groove width (d) is equal to the sum of the height (D) and the distance (D1) of the rotor (d = D1 + D2), the height (D) is 1.6 mm, and the moving distance measurement sensor 80 measures If the rising distance D1 is 0.4 mm, the groove width d becomes 2 mm.

In this invention, the structures of the rotors (56, 56a) at both ends of the measuring element (50) are completely the same, and the outer surfaces of the rotors (56, 56a) match the outer surfaces of the measuring boss (54), so the measuring element (50) It rotates smoothly as if it were a single member, and the rotational movement on one side is directly transmitted to the rotational movement on the other side, so it has the advantage of accurately measuring the groove width (d).

Based on the above description, a method of measuring the groove width using the groove width measuring device 1 of the snap ring assembly of the present invention will be described with reference to FIG. 4. In Figure 4, each step of the groove width measurement method and the configuration of the groove width measurement device related to each step are shown.

First, the assembly 10 of the output shaft portion of the EV reducer is seated on the base 200 (S10).

Next, the fixing jig (6) of the groove width measuring device (1) of the snap ring assembly is lowered to pressurize the upper surface of the first bearing (B1) of the assembly (10) to maintain the vertical state of the assembly (1) stably and reliably. (S12).

Next, advance the measurer (50) across the inside of the support (4) of the groove width measuring device (1) of the snap ring assembly toward the assembly (10) and move it along the upper surface of the first bearing (B1) to the inside of the snap ring groove (30). After entering, the origin is set so that the lowest point of the lower surface of the rotor 56 is in contact with the lower surface (30a) of the snap ring groove (30), and the plane (560) is parallel to the upper surface (30b) of the snap ring groove (30). Ensure alignment (S14).

Next, the measuring probe 50 is rotated to a position where the upper surface of the rotor 56 comes into contact with the upper surface 30b of the snap ring groove 30 and does not rotate anymore (S16).

Next, the vertical movement distance D1 of the connection jig 70 raised by the rotation of the other rotor 56a is detected by the movement distance measurement sensor 80 (S18).

Finally, the preset height (D) of the rotor 56 and the moving distance (D1) measured in step (S18) are added together to determine this as the groove width (d) of the snap ring groove 30 (S20).

Above, preferred embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the embodiments and various modifications are possible. The core of the present invention is to convert the rotational movement of the measuring instrument into the linear movement of the connecting jig, selecting the rotor height at the end of the measuring instrument to be smaller than the groove width of the snap ring groove, and combining the rotor height and the linear movement distance of the connecting jig to create a snap ring groove. The purpose is to determine the groove width, and other configurations of the groove width measuring device 1 other than this can be freely changed in location, shape, and size.

It is obvious that the scope of rights of the present invention extends to matters that are the same or equivalent to the claims described below.

Claims (10)

A device for measuring the groove width of a snap ring assembly. The device includes a measurer installed across the inside of a support, one end of the measurer is inserted into the snap ring groove of the assembly on which the snap ring is mounted, and the other end of the measurer is vertically aligned along the height direction. It is connected to a connection jig that is installed upright and can move up and down in the vertical direction, and the connection jig is connected to a moving distance measuring sensor. As the measuring member rotates, the connecting jig moves linearly, and the moving distance measuring sensor detects the moving distance of the connecting jig. , Groove width measuring device of the snap ring assembly. According to clause 1,
The measuring member includes a central long rod, a measuring boss formed at an end facing the assembly, and a half-moon (arch) shaped rotor formed on the outer surface forming a ring of the measuring boss,
A device for measuring the groove width of a snap ring assembly, wherein the rotor includes a flat surface at the top and a curved portion that is partially shaped like an arc at the bottom. According to clause 2,
When viewed from the side, the outer circumference of the measuring boss and the outer circumference of the curved part of the rotor coincide with each other, so that the curved part of the rotor does not protrude or go inward from the outer circumference of the measuring boss, and the left and right end points of the plane of the rotor are measured. A device for measuring the groove width of the snap ring assembly, which is the same as the outer peripheral point of the boss and forms a chord on the flat surface. According to clause 2,
A device for measuring the groove width of the snap ring assembly, where the height of the rotor is smaller than the groove width of the snap ring groove. According to clause 4,
In the origin alignment state, the lowest point of the lower surface of the rotor is in contact with the lower surface of the snap ring groove, the plane is aligned parallel to the upper surface of the snap ring groove, and when the probe rotates in one direction, the end of the rotor's plane is in contact with the bottom surface of the snap ring groove. A device for measuring the groove width of the snap ring assembly, which rotates to a position where it contacts the upper surface and cannot rotate any further. According to clause 5,
A groove width measuring device of a snap ring assembly in which a second rotor with the same structure as the end facing the assembly is formed on the opposite side of the side facing the assembly of the measuring device, and the rotation of the measuring device rotates the second rotor and the connection jig moves vertically. According to clause 6,
The assembly is an assembly of the output shaft of an EV reducer, and the snap ring groove is formed adjacent to the bearing of the assembly. A device for measuring the groove width of the snap ring assembly. According to clause 6,
A device for measuring the groove width of the snap ring assembly, where the groove width of the snap ring is the sum of the height of the rotor and the moving distance of the connection jig. A method of measuring the groove width using the groove width measuring device of the snap ring assembly of claim 2, the method comprising:
Seating an assembly including a first bearing and a snap ring groove connected to the first bearing on a base;
maintaining the vertical state of the assembly by lowering the fixing jig of the groove width measuring device of the snap ring assembly to press the upper surface of the first bearing of the assembly;
Advance the measuring instrument toward the assembly and enter the inside of the snap ring groove along the upper surface of the first bearing, then set the origin so that the lowest point on the lower surface of the rotor is in contact with the lower surface of the snap ring groove, and the plane is parallel to the upper surface of the snap ring groove. A step of achieving alignment;
Rotating the measuring device to a position where the upper surface of the rotor comes into contact with the upper surface of the snap ring groove and does not rotate anymore;
Detecting the vertical movement distance of the connection jig raised by the rotation of the rotor on the other side of the measuring instrument with a movement distance measurement sensor; and
A groove width measurement method comprising the step of adding the preset height of the rotor and the moving distance measured by the moving distance measurement sensor and determining this as the groove width of the snap ring groove. According to clause 1,
The moving distance measuring sensor is a groove width measuring device of the snap ring assembly, which is an LVDT (Linear Variable Displacement Transducer) sensor.