JPH09196605A - Measuring and assembling method for double-row angular ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a cost for producing a double-raw angular ball bearing. SOLUTION: Balls 18, 19 each having a reference diameter are embedded in at least one of raceway grooves 6, 7 of a case 1. A reference spacer 17 is coaxially interposed between separate type inner races 4, 5, then tentative assembling of a bearing is executed. A movable distance X in the axial direction of the case 1 and the double-row balls 2, 3 between the raceway grooves 6, 7 of the inner race which is extended from the reference spacer 17 is measured. Classes of the double row balls 2, 3 for providing a desired axial clearance to the bearing by being replaced with the balls 18, 19 each having the reference diameter are obtained from the difference between the measured value and a length L of the reference spacer 17. The replacement of the balls is carried out and the reference spacer 17 is removed, then the assembling is completed. Matching measurement is completed in one process so that measuring error is not accumulated, the axial clearance is accurately obtained and total inspection after the completion of the bearing can be needless.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a method for more accurately performing a measurement for obtaining matching of components in a double-row angular contact ball bearing, and a desired axial clearance from a value obtained by the measurement method. A method for assembling a double-row angular contact ball bearing.

[0002]

2. Description of the Related Art The basic structure of a double-row angular contact ball bearing is shown in FIG.
And separate inner races 4 and 5. The case 1 has a cylindrical shape, and two raceway grooves (hereinafter, also referred to as inner ring raceway grooves) 6 and 7 having a predetermined radius R are formed on the inner wall thereof. The balls 2, 3 have a diameter D. The inner races 4 and 5 are symmetrical in the left-right direction in FIG. 5, and raceway grooves (hereinafter also referred to as outer ring raceway grooves) 8 and 9 having a predetermined radius r are formed on the outer walls of the inner races 4 and 5, respectively. Then, the inner ring raceway grooves 6 and 7, the balls 2 and 3, and the outer ring raceway grooves 8 and 9
The contact angle with is at an angle θ with respect to the axis. In the figure
Reference numerals 10 and 11 denote cages for the balls 2 and 3. further,
A flange 12 is press-fitted into the outer wall of the case 1, and a main shaft 13 is press-fitted into the inner walls of the inner races 4 and 5, thereby forming a unit bearing 14 using a double-row angular ball bearing.

By the way, the unit bearing shown in FIG.
14 is what is commonly called the first generation. Further, FIGS. 6 and 7 show second and third generation unit bearings 15 and 16 having a double-row angular contact ball bearing structure, respectively. In the second generation unit bearing 15 shown in FIG. 6, the case 1 and the flange 12 in the first generation are integrated. Further, in the third-generation unit bearing 16 shown in FIG. 7, the inner race 4 and the main shaft 13 in the first and second generations are further integrated. In other words, as progressing from the first generation to the third generation, component parts are integrated and versatility is reduced, but part cost and assembly man-hours are reduced due to the decrease in the number of parts. It is possible to prevent the deterioration of matching due to the accumulation of dimensional errors.

Structural features common to the first to third unit bearings will now be described by taking the third generation unit bearing 16 as an example. FIG. 8 schematically shows the axial clearance C in the double-row angular contact ball bearing structure of the unit bearing 16. The axial clearance C is such that when the end surface 4a of the inner race 4 and the end surface 5a of the inner race 5 integrally formed on the main shaft 13 are brought into close contact with each other, the inner ring raceway grooves 6, 7, balls 2, 3 and the outer ring raceway groove 8 are formed. , 9 is a clearance that is consciously provided in the axial direction (left and right direction in FIG. 8). The axial clearance C shown in FIG. 8 is particularly called a "positive axial clearance", whereby the unit bearing 16 has a certain amount of play in the axial direction.

If the axial clearance C is not intentionally provided, the inner ring raceway grooves 6 and 7, the balls 2 and 3, the outer ring raceway groove 8 may be formed as shown in FIG. There is a possibility that a “negative axial clearance” C ′ may occur between the end surface 4 a of the inner race 4 and the end surface 5 a of the inner race 5 when the inner race 4 and the inner race 9 are in close contact with each other. Then, the end face 4 is formed to fill the negative axial clearance C '.
When the assembling is advanced until a and 5a come into close contact with each other, a force as shown by an arrow F is applied to the balls 2 and 3, and the balls 2 and 3 elastically deform as shown in FIG. 10, so-called "preload" occurs. Will be done. The bearing in which this preload is generated will have an increased rotational resistance and a shortened life. Moreover, since this negative axial clearance occurs at a position where the stylus or the like of the measuring device is hard to enter, it is more difficult to actually measure than before.

For the above reasons, it is necessary to provide a positive axial clearance C in a rolling bearing including a double-row angular contact ball bearing structure. However, if the axial clearance C is too large, rattling also becomes large, and the quality as a bearing is increased. Will decrease. For this reason, the components that make up the double-row angular contact ball bearing structure are finely classified within the range of dimensional tolerances and dimensional control is performed to obtain the optimum matching (variation in dimensional values of each component). Is assembled in the direction of obtaining the desired axial clearance C in the assembled state), and a method for completing the double-row angular ball bearing structure is selected.

By the way, in matching the parts constituting the double-row angular contact ball bearing structure by the conventional method,
Taking the third-generation unit bearing 16 as an example, the dimensions of the case 1 integrated with the flange 12, the inner race 4 and the inner race 5 integrally formed with the main shaft 13 are individually measured by dedicated measuring devices. However, the class (ball diameter) of the ball for obtaining the optimum matching was calculated from these measured values. The dimension measurement performed to obtain the optimum matching is referred to as matching measurement in the following description. As described above, the details are disclosed in Japanese Patent Application Laid-Open No. 58-121322 as a conventional example in which the matching measurement is separately performed for each component of the double-row angular ball bearing structure.

[0008]

However, according to the conventional method of performing matching measurement on a single component and selecting the component constituting the double-row angular contact ball bearing based on the measurement value obtained here, the matching measurement is performed. The number of man-hours required for each part increases according to the number of parts, and when the parts are actually combined, the measurement error of each part may accumulate and the desired assembly accuracy may not be obtained. Sometimes required.

The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to perform matching measurement of a double-row angular contact ball bearing in one stroke. The purpose of the present invention is to enable easy matching and reduce the cost of manufacturing the bearing.

[0010]

Means for Solving the Problems According to the present invention for solving the above problems, an angular contact ball bearing having a case, double rows of balls and a separate inner race has a predetermined groove in the case. Insert a ball of a diameter and interpose a reference spacer of a predetermined length coaxially between the separate inner races to tentatively assemble the bearing, and then insert the raceway groove of the inner race extended by the reference spacer. The axial movable distance of the ball is measured, and the axial clearance of the bearing is obtained from the measured value, the reference spacer length, and the ball diameter.

The above measured values take into consideration constants determined from the ball diameter and bearing specifications (dimensions of each part such as the pitch of double-row balls, case inner ring raceway groove radius, inner race outer ring raceway groove radius). It is a value actually measured including all the relationships among the obtained value, the reference spacer length, and the axial clearance existing at the time of measurement. Among the values that influence the measured value, at least one of the ball diameter and the reference spacer length is a known value, and therefore the unknown axial clearance can be obtained. Further, by extending the pitch between the raceways of the separated inner race by the reference spacer, even if the negative axial clearance is provided, the negative axial clearance is filled by the reference spacer and the negative axial clearance is increased. The measured value is obtained as the value affected by the clearance. That is, even if there is a negative axial clearance, it can be expressed numerically.

Further, a means for solving the above-mentioned problems is to provide a reference diameter in at least one of the raceway grooves of the case of an angular ball bearing having a case, double rows of balls and a separate inner race. Ball is inserted, a reference spacer of a predetermined length is coaxially interposed between the separated inner races, and the bearing is temporarily assembled, and the space between the race grooves of the inner race extended by the reference spacer is inserted. The axial movable distance of the ball is measured, and from the measured value and the reference spacer length, a ball having a diameter giving the desired axial clearance to the bearing by replacing the ball with the reference diameter is selected. Is replaced, the reference spacer is removed, and the assembly is completed.

Except for balls having a reference diameter to be fitted in at least one raceway groove, the components actually forming the double-row angular ball bearing are combined and the axial clearance in the case of the combination is determined. Then, in order to compensate for the difference between the ball having the reference diameter and the desired axial clearance,
Replace with a ball of a different rank. Since the ball diameter before replacement is known, it is easy to select the class of the ball to be replaced, and the final adjustment to obtain the desired axial clearance is exchanged with the ball of the reference diameter, and the class of the ball actually assembled is selected. By.

By the way, the above-mentioned measured values include all the relationships among the values obtained in consideration of the constants determined from the ball diameter and bearing specifications, the reference spacer length, and the axial clearance existing at the measurement stage. It is the value actually measured. Among the values that influence the measured value, the reference spacer length and the set value of the axial clearance are known values, and therefore, the rank of the ball that is an unknown value (the desired axial clearance is obtained. You can ask for a class). Further, by extending the pitch between the raceways of the separated inner race by the reference spacer, even if the negative axial clearance is provided, the negative axial clearance is filled by the reference spacer and the negative axial clearance is increased. The measured value is obtained as a value affected by the clearance. That is, the existence of the ball can be numerically expressed regardless of the positive and negative axial clearances, and the class of the ball for correcting to the desired axial clearance can be determined.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. In the figure, the same or corresponding parts as those of the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

First, the first embodiment of the present invention will be described. In this embodiment, the axial clearance of the unit bearing 16 having the double-row angular ball bearing structure shown in FIG. 7 is obtained, and the parts for optimal matching are selected based on the value of the axial clearance. is there. The unit bearing 16 includes a case 1 integrally formed with the flange 12 and two rows of balls 2, 3
And separate inner races 4 and 5, the inner race 4 is integrally formed with the main shaft 13, and the inner race 5 is press-fitted into the main shaft 13. The case 1 has a tubular shape and has two raceway grooves (also referred to as inner ring raceway grooves) 6 each having a predetermined radius R on its inner wall.
7 are formed. The balls 2, 3 have a diameter D. The inner races 4 and 5 are symmetrical with each other in the left-right direction of FIG. The contact angle between the inner ring raceway grooves 6 and 7, the balls 2 and 3 and the outer ring raceway grooves 8 and 9 forms an angle θ with respect to the axis. Therefore, it is possible to receive both the thrust load and the radial load. The balls 2 and 3 are supported by cages 10 and 11 so that the positional relationship between the balls is constant.

In the present embodiment, the matching measurement required for obtaining the axial clearance of the unit bearing 16 composed of the above parts is performed in one stroke regardless of the number of parts. To prepare for this,
The reference spacer 17 is attached to the unit bearing 16 as shown in FIG.

As shown in FIG. 3, the reference spacer 17 has a tubular shape having a large diameter portion 17a and a small diameter portion 17b, and both the inner tubular portion and the outer tubular portion are formed in two stages. The large-diameter portion 17a is precisely dimensioned and processed into a predetermined length L. This length L is called the length of the reference spacer 17. Then, as shown in FIG. 2, the inner race 4 and the inner race 5 are
And the pitch between the inner race raceway grooves 8 and 9 is extended by the length L of the large diameter portion 17a. Further, it has a role of guiding movement of the case 1 and the balls 18 and 19 in the axial direction at the time of measurement described later.

By the way, the inner diameter d ₁ of the large diameter portion 17a shown in FIG. 3 is substantially the same as the outer diameter of the cylindrical portion 13a (see FIG. 2) of the main shaft 13 into which the inner race 5 is press fitted. The outer diameter d ₂ of the large diameter portion 17a is substantially the same as or slightly smaller than the outer diameters of the inner races 4 and 5 as shown in FIG. Further, the inner diameter d ₃ of the small diameter portion 17b without contacting the distal end threaded portion 13b of the spindle 13 shown in FIG. 2, and the small diameter portion in consideration of the outer diameter d ₄ 17
The diameter should be sufficient to secure the meat pressure of b. The outer diameter d ₄ of the small diameter portion 17b is the inner cylindrical portion 5a of the inner race 5 (see FIG. 2).
It has a diameter that can be inserted into.

Further, as another preparation for performing the matching measurement in the present embodiment, balls 18 and 19 each having a reference diameter D _S are arranged in the raceway grooves 6 and 7 of the case 1 shown in FIG. To do. That is, at this point, the length L of the reference spacer 17 and the diameter D _{S of the} balls 18 and 19 have known values. Then, the fixing nut 20 is screwed into the tip screw portion 13b of the main shaft 13, and the unit bearing 16 is temporarily assembled with the reference spacer 17 interposed between the inner race 4 and the inner race 5. By the way, spindle 13
The center hole 13c is used to engage the gauge 22 of the measuring device 21 shown in FIG. 4 in the matching measurement described later. Furthermore, the hole of the flange 12 integrated with the case 1
The fixing bolt 23 (see FIG. 4) for fixing the unit bearing 16 to the measuring device 21 can be inserted through the 12a.

The procedure of matching measurement for obtaining the axial clearance will be described below. FIG. 4 shows an example of a measuring device that performs matching measurement. The measuring device 21 has a reversing shaft 25 which is horizontally supported by a base 24 and is rotatable. The reversing shaft 25 has a unit bearing 16
A fixing portion 26 for fixing the armature 22 and an arm 27 for supporting the gauge 22 in a positionally adjustable manner are provided. Then, the flange 12 of the unit bearing 16 is fixed to the fixing portion 26 of the reversing shaft 25.
And the fixing bolt 23 is inserted into the hole 12a (see FIG. 2) and bolted. Further, the arm 27 is adjusted to bring the gauge head 22a of the gauge 22 into close contact with the center hole 13 (see FIG. 2) formed in the main shaft 13 of the unit bearing 16. When the reversing shaft 25 is rotated, the unit bearing 16 and the gauge 22 rotate together with the reversing shaft 25.

FIG. 1 shows how the matching measurement is performed. By the way, in the bearing unit 16 temporarily assembled in the state of FIG. 2, the case 1 and the balls 18 and 19 are integrally formed between the raceway grooves 8 and 9 of the inner races 4 and 5 extended by the reference spacer 17. Therefore, it is possible to move in the axial direction. Then, when the reversing shaft 25 is rotated as described above, the main shaft 13 shifts from the state on the left side in FIG. 1 to the state on the right side (or the opposite direction) due to its own weight. That is, the movable distance in the axial direction of the case 1 and the balls 18 and 19 can be measured as the displacement amount X of the main shaft 13 (hereinafter, also referred to as a measurement value X).

By the way, in the double-row angular bearing structure,
The following relationships are established. C = X−L−k · D _S (I) where C: Axial clearance X: Measured value L: Reference spacer length D _S : Reference ball diameter k: Constant determined by bearing specifications. As mentioned above, the length L of the reference spacer 17 and the balls 18, 19
Since the diameter D _S and the constant k are known values and the measured value X is an actually measured value, the value of the axial clearance C can be obtained by substituting each value into the mathematical expression (I).

Assuming that the desired axial clearance in the unit bearing 16 is C _A , the difference between the obtained axial clearance C and the desired axial clearance C _A is compensated by changing the diameters of the balls 18 and 19. For example,
You have completed the matching. Therefore, the reference diameter D _S
In place of the balls 18 and 19, the balls 2 and 3 of the class capable of obtaining the axial clearance C _A are selected and fitted. Then, the reference spacer 17 is removed, and the spindle 13 shown in FIG.
The inner cylindrical portion 5a of the inner race 5 is press-fitted into the cylindrical portion 13a, and the fixing nut 20 is further tightened to complete the assembly of the third-generation unit bearing 16 having the double-row angular contact ball bearing structure.

The operation and effect of the first embodiment of the present invention having the above structure are as follows. The measured value X is
It is a value that is actually measured, including the relationship between the value obtained from the product of the diameter D _{S of the} balls 18 and 19 and the constant k, the length L of the reference spacer 17, and the axial clearance C. Therefore, using this relationship, the unknown value of the axial clearance C can be obtained from the known value of the ball diameter D _S and the reference spacer length L, and the measured value X.

Moreover, when obtaining the axial clearance,
The raceway groove 8 of the inner races 4 and 5 by the reference spacer 17
Since the pitch between 9 is extended, even if the combination of case 1, balls 18, 19 and inner race 4 and inner race 5 has a negative axial clearance C '(see FIG. 9), The reference spacer 17 fills the axial clearance C ′, and the displacement amount X is measured as X = L + k · D _S + C ′ (a modification of the formula (I), C ′ is a negative value). That is, the negative axial clearance C ′, which has been difficult to measure in the past, can be expressed as a measured value in which the displacement amount X is changed. Therefore, the case 1, ball 18,
19, it is possible to numerically represent the axial clearance by combining the inner race 4 and the inner race 5 regardless of whether the value is positive or negative. Therefore, based on this measured displacement amount X, the desired axial clearance C
It is possible to obtain the class of the balls 2 and 3 used in the actual assembly for obtaining _A.

Then, the balls 18 and 19 having the reference diameter D _S are exchanged with the balls 2 and 3 (having a class capable of filling the difference between the calculated axial clearance C and the desired axial clearance C _A ). . That is, the matching for obtaining the desired axial clearance C _A can be obtained by selecting the class of the ball to be replaced with the ball having the reference diameter. In this way, the matching measurement for determining the axial clearance C of the unit bearing 16 having the double row angular contact ball bearing structure is performed in one stroke, and the measurement error is prevented from being accumulated due to the measurement over a plurality of strokes, and the matching is performed. The unit bearing 16 can be obtained.

Next, a second embodiment of the present invention will be described. Here, description of the same or corresponding portions as those in the first embodiment will be omitted. By the way, the difference between the second embodiment and the first embodiment is that in the unit bearing 16 of the third generation shown in FIG.
(That is, the ball that is actually incorporated) is inserted into the raceway groove 7
The ball 19 having the reference diameter D _S is arranged in the position. Then, the displacement amount X of the spindle 13 is measured as in the first embodiment. In this case, the diameter of the ball 2 actually incorporated is also added to the measured value X, and in order to obtain the desired axial clearance C _A , the ball class of the ball 3 that replaces the ball 19 having the reference diameter D _S. ΔD can be directly calculated.

At this time, the following relationships are established. C _A = X−L−k · ΔD (II) where C _A : desired axial clearance ΔD: class of balls for obtaining desired axial clearance As described above, desired axial clearance C _A and reference The length L of the spacer 17 is a known value, and the measured value X is actually measured. Therefore, by substituting each value into the formula (II), the ball class ΔD for obtaining the desired axial clearance can be obtained. Value is required. Other than that, the description of the same effects as those of the first embodiment will be omitted.

By the above method, it is possible to obtain the finished product of the third generation unit bearing 16 shown in FIG. In the above description, the third-generation unit bearing 16 has been taken as an example, but a reference spacer having a predetermined length is interposed in the separated inner race to set the pitch between the raceway grooves of the inner race. The method of measuring the movable distance between the case and the ball by using the ball that has a longer diameter and has a reference diameter can also be applied to the first and second generation unit bearings 14 and 15 shown in FIGS. 5 and 6. Moreover, even if the number of parts increases, the matching measurement can be performed in one stroke, so there is no accumulation of measurement error, and the ball of the reference diameter can be replaced by a ball of the desired grade. Axial clearance can be obtained.

[0031]

According to the present invention, the following effects are obtained. That is, in an angular contact ball bearing having a case, multiple rows of balls, and a separated inner race, a reference spacer is interposed between the inner races,
By measuring the axial movable distance of the case and the double-row balls between the raceway grooves of the extended inner race, even if there is a negative axial clearance, the reference spacer fills the negative axial clearance, The measured value is obtained as a value affected by the negative axial clearance.
Therefore, it is possible to numerically represent the negative axial clearance, which has been difficult to measure in the past, and it is possible to know the class of the ball for correcting the negative axial clearance to obtain the desired axial clearance.

Further, a ball having a reference diameter is fitted in at least one of the raceway grooves of the case, and a reference spacer is coaxially interposed between the separated inner races to temporarily assemble the bearing, and then the measurement is performed. By taking into account the measured values, the constants determined from the ball diameter and bearing specifications (double row ball pitch, case inner ring raceway groove radius, inner race outer ring raceway groove radius, etc.) are taken into consideration. It can be measured as a value that includes all of the relationship between the value obtained by the above, the reference spacer length, and the axial clearance existing at the time of measurement. By the way, at least one of the ball diameter and the reference spacer length is a known value, and it is possible to obtain the unknown axial clearance by further obtaining the measured value.

Further, from the difference between the measured value and the reference spacer length, it is possible to substitute the ball having the reference diameter to obtain the class of the ball for providing a desired axial clearance in the bearing. By replacing the balls of the reference diameter with the balls of the obtained class, the bearings are matched and the reference spacer is removed,
The assembly of the double-row angular contact ball bearing can be completed.

That is, in the present invention, the reference spacer is interposed between the components of the double-row angular contact ball bearing before the completion of the assembly, the balls are replaced with the balls having the reference diameter, and the temporary assembly is performed. For the desired axial clearance,
Furthermore, since it is possible to achieve matching to obtain the desired axial clearance, even for different types of double-row angular contact ball bearings, use a reference spacer and a reference diameter ball corresponding to each bearing. This allows for easy adaptation. In addition, since the same measuring device can be used regardless of the type of bearing, it is highly versatile, and it is possible to obtain a highly accurate axial clearance at low cost and obtain a matched bearing. Since it is not necessary to inspect all products after completion, the cost for manufacturing the double-row angular contact ball bearing can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing how a matching measurement is performed according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a mounted state of a reference spacer used for the matching measurement shown in FIG.

FIG. 3 is a sectional view of a single unit of the reference spacer shown in FIG.

FIG. 4 is a schematic diagram showing a measuring device used for the matching measurement shown in FIG.

FIG. 5 is a partial cross-sectional view of a first generation unit bearing.

FIG. 6 is a partial cross-sectional view of a second generation unit bearing.

FIG. 7 is a cross-sectional view of a third generation unit bearing.

8 is a partial cross-sectional view schematically showing the positive axial clearance in the third-generation unit bearing shown in FIG.

9 is a partial cross-sectional view schematically showing the negative axial clearance in the third-generation unit bearing shown in FIG.

10 is a partial cross-sectional view schematically showing a state in which preload has occurred in the third-generation unit bearing shown in FIG.

[Explanation of symbols]

 1 case 2 ball 3 ball 4 inner race 5 inner race 6 raceway groove 7 raceway groove 8 raceway groove 9 raceway groove 13 spindle 16 third-generation unit bearing 17 standard spacer 18 ball 19 ball

Claims (2)

[Claims] 1. An angular contact ball bearing having a case, a double row of balls and a separable inner race, a ball having a predetermined diameter is fitted in a raceway groove of the case, and a reference of a predetermined length is provided between the separable inner races. The bearing is tentatively assembled with the spacer interposed coaxially, and the axial movable distance of the ball between the race grooves of the inner race extended by the reference spacer is measured. A method for measuring a double-row angular contact ball bearing, characterized in that the axial clearance of the bearing is obtained from the spacer length and the ball diameter. 2. An angular contact ball bearing having a case, a double row of balls and a separated inner race, a ball having a reference diameter is fitted in at least one of the raceway grooves of the case, and a predetermined gap is provided between the separated inner races. The bearing is tentatively assembled with a long reference spacer interposed coaxially, and the axial movable distance of the ball between the race grooves of the inner race extended by the reference spacer is measured. From the length of the reference spacer, select a ball having a diameter that gives the desired axial clearance to the bearing by replacing it with the ball having the reference diameter, replace the ball, and remove the reference spacer to assemble. A method for assembling a double-row angular contact ball bearing, characterized by completing the above.