JPH01172630A - Adjustment of ball spline - Google Patents

Abstract

PURPOSE:To prevent the shift trouble of a movable body by selecting the diameter of a ball so as to be set within a prescribed clearance for the inside diameter which is formed by a ball groove formed on the inner peripheral surface of a movable body and a ball groove formed on the outer peripheral surface of the shaft. CONSTITUTION:Each semicircular ball groove 51 is formed at three positions on the circumference of the outer peripheral surface 20a of a primary shaft 20, and a semiciucular ball groove 52 is formed also on the inner peripheral surface 36c of a movable pulley 36b. A plurality of a balls 53 are inserted by oppositely setting the ball grooves 51 and 52. If a dimension dispersion exists between the ball groove 51 and 52 in such constitution, acting force varies even if the diameter of the ball 53 is equal. Therefore, each ball groove 51, 52 is measured, and the evaluation clearance in the case when the ball having a standard diameter is inserted is calculated. Then, the diameter of the ball 53 is selected so that the evaluation clearance is set within a prescribed range.

Description

[Detailed description of the invention] [Industrial application field]

The present invention forms a ball spline ball groove between an axially movable movable body and a support shaft, and adjusts the clearance by selecting the ball diameter so as to equalize the clearance between the ball spline groove and the ball. Regarding how to.

[Conventional technology]

Conventionally, for example, regarding the support of the movable pulley of a continuously variable transmission, JP-A-Sho! Publication No. 57-139759, Utility Model Application No. 62-1
The prior art disclosed in Japanese Patent No. 28259 discloses that the movable side of each pulley is supported with respect to the shaft by a ball spline, and the movable pulley is moved in the axial direction and the speed is smoothly changed.

[Problems to be solved by the invention]

By the way, the above-mentioned ball spline is constructed by forming semicircular ball grooves on the inner circumferential surface of the movable pulley and the outer circumferential surface of the shaft, and inserting balls between both ball grooves, so variations in the dimensions of the ball grooves may occur. The size of the ball has a large influence on the operating force of the movable pulley depending on the size of the ball diameter, etc. In other words, the size of the ball should be selected and assembled so that it has a clearance that can accommodate variations in the dimensions of the ball groove. If the ball is large in relation to the ball groove, the clearance between the two will be small and the movable pulley's operating force will increase.
The gear shifting speed becomes slow and the gear shifting followability is lacking. vice versa,
If the ball is small, the clearance between the ball groove and the ball is large, and the shaft and movable pulley are not tight enough, causing play, which causes the belt element to tilt and strain the female surface of the pulley circle, causing wear. There is a risk that excessive force will be applied to the belt itself, causing it to break. Therefore, when assembling the ball spline, it is necessary to manage the movable pulley operating force so as to equalize it. In view of these points, it is an object of the present invention to provide a ball spline adjustment method that uniformly adjusts the clearance when a ball is inserted into a ball groove formed in a movable body and a shaft.

[Means to resolve the gap]

In order to achieve the above object, the present invention provides a ball spline formed between a movable body and a shaft, which is formed by a ball groove formed on the circumferential surface of the movable body and a ball groove formed on the outer circumferential surface of the shaft. An evaluation clearance is determined based on the inner diameter of the ball and the reference ball diameter, and based on the evaluation clearance, the diameter of the ball is selected so as to fall within a predetermined clearance range that provides a preset movable body operating force. The assembly is performed by adjusting the clearance between the ball groove and the ball.

[For production]

Based on the above configuration, in the ball spline, balls with predetermined diameters that are suitable for the size of the ball groove on the movable body side and the size of the ball groove on the shaft side are selected to equalize the movable body actuation force. It is possible to eliminate problems caused by backlash and malfunction of the ball spline. [Implementation PA] Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings. In FIG. 1, an example of a belt-type continuously variable transmission to which the present invention is applied will be described. Reference numeral 1 is an electromagnetic powder clutch, 2 is a continuously variable transmission, and the continuously variable transmission l12 is roughly divided into Switching section for forward and backward movement from the side 3. The pulley ratio conversion section 4 and the final reduction section 5 are configured to be transmission-driven. The electromagnetic powder clutch 1 is housed in one side of the clutch housing 6, and is connected to the other side of the clutch housing 6, the main case 7 connected thereto, and the side of the main case 7 opposite to the clutch housing 6. Inside the side case 8, there is a switching section 3 for the continuously variable transmission lI2. A pulley ratio conversion section 4 and a final reduction section 5 are assembled. The electromagnetic powder clutch 1 is connected to the crankshaft 10 from the engine.
A ring-shaped drive member 12 is integrally connected to the drive plate 11 via the drive plate 11. It has a disk-shaped driven member 14 that is integrally spline-coupled to the transmission input shaft 13 in the rotational direction. A coil 15 is built into the outer peripheral side of the driven member 14, and a gap 16 is formed along the circumference between the drive member 12 and the driven member 14, and this gap 16 is a powder chamber containing electromagnetic powder inside. It communicates with 17. In addition, a power supply brush 19 is in sliding contact with a slip ring 18 of the hub portion of the driven member 14 equipped with a coil 15, and is further connected to the coil 15 through the inside of the driven member 14 from the slip ring 18 to form a clutch current circuit. ing. In this way, when a clutch current is passed through the coil 15, the drive member 12 and the driven member 1 are connected through the gap 16.
4, electromagnetic particles are combined and accumulated in the gap 16 in a chain shape, and the resulting binding force causes the driven member 14 to slide and integrally connect with the drive member 12, resulting in the clutch 8111 state. Become. On the other hand, when the clutch current is cut, the coupling force between the drive member 12 and the driven member 14 due to the electromagnetic powder disappears, resulting in a clutch disengaged state. Then, the clutch current control in this case is continuously variable 3t[
If it is performed in conjunction with the operation of the switching section 3 of I12,
Forward drive (D), sporty drive (Ds) from parking (P) or neutral (N) range
Alternatively, when switching to the reverse (R) range for reversing, clutch 1 is automatically disengaged, making it unnecessary to operate the clutch pedal. Next is stepless 3m! At 682, the switching section 3 is provided between the input shaft 13 from the clutch 1 and the primary shaft 20 disposed coaxially therewith. That is, input shaft 1
3 is formed with a gear 21 for a reverse drive that also serves as a forward engaged side, and a gear 21 on a reverse engaged side is formed on the primary shaft 20.
2 are rotatably fitted, and these gears 21 and 22
are meshed through a counter gear 24 supported by a shaft 23 and an idler gear 26 supported by a shaft 25. A cut ellipse 27 is provided between the primary shaft 2o and the gears 21 and 22. Here, the gears 21, 24, 26, 22, which are always in mesh, are connected to the driven member 14 having the coil 15 of the clutch 1, and this corresponds to the fact that the inertia mass of this part is relatively large when the clutch is disengaged. In the switching mechanism 27, the sleeve 29 spline-fitted to the hub 28 of the primary shaft 20 is connected to the synchronizing mechanism 30.
．． 31 to be meshed and coupled to each gear 21, 22. As a result, in the neutral position of the P or N range, the sleeve 29 of the switching mechanism 27 is fitted only with the hub 28, and the primary shaft 20 is separated from the input shaft 13. When engaged with the gear 21 side, the primary shaft 2° is directly connected to the input shaft 13, resulting in the forward state of the D or DS range. On the other hand, when the sleeve 29 is reversely engaged with the gear 22 side via the synchronizing mechanism 31, the input shaft 13 is connected to the gear 21.
It is connected to the primary shaft 20 through 26 and 22, and the engine power is decelerated and reversed to enter the R range reverse state. In the pulley ratio converter 4, a secondary shaft 35 is arranged parallel to the primary shaft 20, and these primary shafts 2
0. A primary pulley 36 is attached to each secondary shaft 35.
．． A secondary pulley 37 is provided, and an endless drive belt 34 is provided between the primary pulley 36 and the secondary pulley 37. Primary pulley 36. Each of the secondary pulleys 37 is divided into two parts, one of which is a fixed pulley 36a. In contrast to 37a, the other movable pulleys 36b and 37b (movable bodies) are movable to make the pulley interval variable, and each of the movable pulleys 36b and 37b is attached with a hydraulic servo device 38, 39 which also serves as a piston. Further, a spring 40 is applied to the movable pulley 37b of the secondary pulley 37 in a direction to narrow the pulley interval. Further, as a hydraulic control system, an oil pump 41 as an operating source is installed next to the primary pulley 36. This oil pump 41 is a high-pressure gear pump, and the pump drive shaft 4
2 is 1 primary pulley 36. It penetrates through the inside of the primary shaft 20 and the input shaft 13 and is directly connected to the crankshaft 10, so that oil pressure is constantly generated during engine operation. -Then, the oil pressure of this oil pump 41 is controlled to supply and drain oil to each hydraulic servo device 38, 39, and the primary pulley 36
By changing the pulley spacing between the primary pulley 36 . The pulley ratio in the secondary pulley 37 is continuously changed, and the continuously variable power is output to the secondary shaft 35. In view of the fact that the minimum pulley ratio on the high-speed stage side of the pulley ratio converter 4 is very small, for example 0.5, and therefore the number of rotations of the secondary shaft 35 is high,
5, an output shaft 44 is connected to the output shaft 44 via one set of intermediate reduction gears 43. The drive gear 4 of this output shaft 44
The final gear 46 meshes with 5, and the final gear 46
from the left and right drive wheel axles 48 through the differential IN mechanism 47.
49, transmission is configured. Therefore, each movable pulley 36b, 37b of the primary pulley 36 and secondary pulley 37 is attached to the primary shaft 2.
0, loosely fitted to the secondary shaft 35, ball spline 50
axial movement is supported very smoothly. For example, referring to the ball spline 50 on the primary side in FIGS. 2(a) and 2(b), the primary shaft 2
Semicircular ball grooves 5 are provided at three locations on the circumference of the outer peripheral surface 20a of 0.
1 is formed, and the inner peripheral surface 3 of the movable pulley 36b is similarly formed.
A semicircular ball groove 52 is also formed in 6c, and a plurality of balls 5 are inserted therein by making these ball grooves 51 and 52 face each other.
3 are inserted in a row. Here, the balls 53 roll to promote smooth movement of the movable pulley 36b and to eliminate looseness between the primary shaft 20 and the movable pulley 36b, and are therefore inserted into the ball grooves 51 and 52. Therefore, it can be seen that the axial movement of the movable pulley 36b requires an actuation force F, and by setting this actuation force F within a predetermined range, it is possible to satisfy both the shifting speed and the effect of reducing backlash. On the other hand, the respective ball grooves 51 and 52 on the shaft side and the pulley side have dimensional variations during machining, and when they are opposed to each other, they are affected by the variations in both. Therefore, even if the diameters of the balls 53 are the same, the balls? 1151
It is clear that the above-mentioned operating force F fluctuates due to the variation in the dimension of 52 degrees, and for this, each ball groove 51,
It is necessary to adjust the diameter of the ball 53 with respect to the dimension of the ball 52. Here, a method for quickly and appropriately selecting the diameter of the ball 53 will be described. First, the movable pulley (movable body) operating force F has a correlation with the clearance γ in the combination of the ball grooves 51, 52 and the balls 53, and in order to set the operating force F within a predetermined range, the clearance γ must be set within a predetermined range. It was found that it would be better to set it within a certain range. Therefore, each ball groove 5
1,52, and compared to this ball 5 with the standard ball diameter.
Calculate the evaluation clearance γ when inserting ball 5, and adjust the ball 5 so that this evaluation clearance γ falls within a predetermined range.
3 diameters are selected. Here, a ball with a standard ball diameter is inserted into the shaft side ball groove 51, and the values a1 to a4 obtained by measuring the clearance in that case are classified into four classes A to D. Similarly, the values b1 to b4 obtained by inserting the ball and measuring the clearance in that case are 4.
They are divided into two classes A' to Do and combined as shown in the table below. In this case, al < a2 < a3
<aa. bl * b2 * b3 * b4. Then, the class A-A' of a4 and bl, the class B-B' of a3 and b2, the class C-C' of a2 and b3, and the class D-D' of a1 and b4 are the standard ball diameter d of the ball 53. The evaluation clearance γ is set approximately equal to . And in the combination of a4 of class A on the shaft side and b2 of class B° on the pulley side, bl x b
2, the evaluation clearance γ is smaller than the combination of a4 and bl, so the ball diameter is increased accordingly to d+χ1, and in the square alignment with b3 of pulley side class C", b
Since 2 x b3 x b4, the ball diameter is set to be larger than d+χ2. Conversely, in the combination of bl of pulley side class A'' and a3 of shaft side class B, the evaluation clearance γ is smaller than the combination of a4 and bl due to the relationship al < a2, so the ball diameter is d- χ1, and create a table in which the clearance is approximately constant as shown below. Table Then, insert a ball with the standard ball diameter into the shaft side ball groove 51 and measure the clearance in that case, a1 to a4, and insert a ball with the standard ball diameter into the pulley side ball groove 52 and calculate the clearance in that case. In various combinations of the measured values b1 to b4, the diameter of the ball 53 is determined and assembled based on the combination of the corresponding classes with reference to the above clothing. This allows ball spline 5
0 means that the movable boob operating force F as well as the clearance has a performance that is approximately equalized with respect to variations in ball groove dimensions. It should be noted that this is performed in the same manner on the secondary pulley side, and the setting values of the operating force and clearance may be the same or different. Although this embodiment has been explained using a ball spline for a continuously variable transmission, it is also applicable to a ball spline for a general mechanical device.

【Effect of the invention】

As described above, according to the present invention, in a ball spline that supports a movable body, the ball diameter is selected in response to variations in ball groove dimensions, and the clearance is adjusted so that the operating force of the movable body falls within a predetermined range. Since the adjustment is made, it is possible to prevent play between the movable body and the shaft and malfunction of the movable body.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the continuously variable transmission of the present invention, FIG. 2(a) is an enlarged sectional view of the main part, and FIG. 2(b) is a BB sectional view. 20...Primary axis, 35...Secondary axis, 3
6b. 37b...Movable pulley (movable body), 50...Ball spline, 51.52...Ball pickle, 53...Ball Patent applicant Fuji Heavy Industries Co., Ltd. Agent Patent attorney Nobu Kobashi Jundo Patent attorney Susumu Murai Figure 2 (b)

Claims (1)

[Scope of Claims] A ball spline formed between a movable body and a shaft, an inner diameter formed by a ball groove formed on the circumferential surface of the movable body and a ball groove formed on the outer circumferential surface of the shaft; An evaluation clearance is determined based on the reference ball diameter, and based on the evaluation clearance, the diameter of the ball is selected so that it falls within a predetermined clearance range that provides a preset movable body operating force, and A ball spline adjustment method characterized by adjusting the clearance with the ball and assembling it.