JP3834784B2 - Water pump bearings - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water pump bearing, and more particularly to a water pump bearing of a type in which both of two rows of bearing raceways formed between a pump shaft and an outer ring are ball raceways.
[0002]
[Prior art]
In a water pump bearing, generally, a raceway surface for two bearing inner rings is formed on the outer peripheral surface of a pump shaft, one end of which is engaged with the impeller and the other end of which is engaged with the pulley, with a predetermined interval in the axial direction. Two rows of rolling bearings formed between the outer ring and the pump shaft, in which the inner ring of the bearing is also used, and the outer ring having two raceways formed on the inner circumference corresponding to each raceway is fixed to the water pump housing. A structure in which a plurality of rolling elements are arranged on each track is adopted.
[0003]
In this type of bearing, as shown in a cross-sectional view in FIG. 2, each of the two rows of rolling bearing races formed between the pump shaft 101 and the outer ring 102 is used as a ball raceway, and a ball row 103 is provided for each. As shown in a sectional view in FIG. 3, a type in which a double row deep groove ball bearing is configured substantially, and the impeller side of the two rows of rolling bearing raceways formed between the pump shaft 201 and the outer ring 202. Two types are mainly used, which are composed of a composite bearing composed of a deep groove ball bearing and a cylindrical roller bearing, in which a ball train 203 is provided with I as a ball raceway and a roller train 204 is provided with a pulley side P as a roller raceway. Yes.
[0004]
[Problems to be solved by the invention]
By the way, among the above two types of water pump bearings, the type in which both rows are ball rows can reduce the manufacturing cost, but the problem is that the rated load is small and the life is shortened under high loads. is there.
[0005]
On the other hand, the combination of the ball row and the roller row has a higher rated load of the roller row and a longer life under high load than the type with both ball rows, but the manufacturing cost is high, and There is a problem that the weight also increases.
[0006]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a water pump bearing that has a high rated load and is cheaper and lighter than a combination of a ball row and a roller row.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a water pump bearing according to the present invention includes a pump shaft in which two ball bearing inner ring raceway surfaces are formed on the outer peripheral surface at predetermined intervals in the axial direction, and the inner peripheral surface includes the above-mentioned An outer ring having two ball bearing outer ring raceway surfaces formed at intervals, and a plurality of balls disposed in two rows of ball raceways formed between the raceway surfaces of the pump shaft and the outer ring. In the water pump bearing used in a state where one end of the pump shaft is engaged with the impeller and the other end is engaged with the pulley, and the outer ring is fixed to the water pump housing , at least one of the two rows of ball raceways. Any one of them is characterized by a four-point contact type ball trajectory.
[0008]
In the present invention, among the ball trajectory of the two rows, that the ball raceway of the four-point contact type ball trajectory pulley side (claim 2) is rather desirable, in that case, at the same opposite side For the ball raceway, that is, the impeller side ball raceway, a deep groove type configuration (Claim 3) can be suitably employed.
The present invention is intended to achieve the intended object by employing a four-point contact ball bearing having a high load capacity.
[0009]
That is, it is known that a four-point contact ball bearing in which a ball as a rolling element contacts the inner and outer rings at two points has a rated load of about 1.5 times that of a normal deep groove ball bearing. The four-point contact ball bearing is basically a ball bearing, and therefore has a lower manufacturing cost and is lighter than a cylindrical roller bearing. Therefore, in the present invention, two rows of rolling bearing raceways formed on the water pump bearing are both used as ball raceways and two rows of ball rows are provided, and at least one of the ball raceways is a four-point contact type. As a result, a water pump bearing that is low in cost and light in weight and has a high rated load is realized.
[0010]
The present invention includes both a configuration in which only one of the two rows of ball tracks has a four-point contact type and a configuration in which both have a four-point contact type, but only either one has four points. In the case of the contact type, as in the invention according to claim 2, it is reasonable to use a four-point contact type on the pulley side ball raceway that requires a greater load resistance. Compared to the case where a roller array is employed to ensure load resistance, a lightweight water pump bearing can be obtained at a low cost while having equivalent load resistance. In this case, the impeller side ball raceway is a deep groove type ball raceway, in other words, a normal two-point contact type used for deep groove ball bearings, as in the invention according to claim 3. Thus, it is possible to obtain a low-cost water pump bearing while improving the overall overload resistance.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an axial parallel sectional view showing the configuration of the embodiment of the present invention.
The pump shaft 1 is used in a state where a pulley (not shown) is attached to one end side indicated by A in the drawing and an impeller (not shown) is attached to the other end side indicated by B in the drawing. On the outer peripheral surface of the pump shaft 1, two ball raceway surfaces 11 and 12 for the inner ring are formed at a predetermined interval in the axial direction.
[0012]
The outer ring 2 is used in a state of being fixed to a water pump housing (not shown). On the inner peripheral surface of the outer ring 2, two ball raceways 21 and 22 for the outer race are formed at positions corresponding to the two ball raceways 11 and 12 of the pump shaft 1, respectively.
[0013]
A ball raceway 31 formed by one ball raceway surface 11 of the pump shaft 1 and one ball raceway surface 21 of the outer ring 2 facing it, the other ball raceway surface 12 of the pump shaft 1 and the other of the outer ring 2 facing it. A plurality of balls 3 are arranged so as to be able to roll on the ball tracks 32 formed by the ball track surfaces 22, and the respective balls 3 are held by the cages 41 and 42 in the respective ball tracks 31 and 32. Are held at regular intervals in the circumferential direction.
[0014]
Further, on the outside of each ball raceway 31, 32, sealing seals 51, 52 are provided for preventing entry of foreign matters such as water from the outside. The outer peripheral portion is fixed by being fitted into seal grooves 2 a and 2 b formed in the inner peripheral portion of the outer ring 2 which is a fixed ring, and the lip formed in each inner peripheral portion is in close contact with the outer peripheral surface of the pump shaft 1. It is like that.
[0015]
Of the two ball tracks 31 and 32 formed between the pump shaft 1 and the outer ring 2, the impeller side ball track 32 is a normal deep groove type, but the pulley side ball track 31 has four points. It is a contact type. That is, the ball raceway surface 11 of the pump shaft 1 and the ball raceway surface 21 of the outer ring 2 are known four-point contact type raceway surfaces in which two circular arcs are combined. , 21 and the balls in the ball raceway 31 roll while contacting the raceway surface 11 and the raceway surface 21 at two points.
[0016]
According to the above embodiment of the present invention, the pulley-side ball raceway 31 on which a larger load acts is a four-point contact type raceway. Therefore, the rated load of this pulley-side ball train is Compared to the case where a normal deep groove type ball train is used, the rated load of the water pump as a whole is larger than that when using a deep groove type ball train. Greatly increased. In addition, since both of the two rows employ ball rows, the manufacturing cost can be kept lower than when one of the rows is a roller row, and the weight does not increase.
[0017]
In the above embodiment, only the pulley-side ball track 31 of the two rows of ball tracks 31 and 32 is a four-point contact type, but both the ball tracks 31 and 32 may be a four-point contact type. Further, only the impeller side ball raceway 32 can be a four-point contact type, and in this case, a lighter weight effect can be expected by using a smaller ball row as the impeller side ball row with a relatively small working load. can do.
[0018]
【The invention's effect】
As described above, according to the present invention, in the water pump bearing provided with two rows of ball rows, at least one of the ball rows is a four-point contact type. Thus, the rated load can be increased without a large cost increase. In particular, by adopting a four-point contact type for the pulley-side ball train on which a larger load acts, it has a rated load comparable to that of a conventional water pump bearing using a roller train, but with a low load. A lightweight water pump bearing can be obtained at a low price.
[Brief description of the drawings]
FIG. 1 is an axial parallel sectional view of an embodiment of the present invention.
FIG. 2 is an axial parallel sectional view showing a configuration example of a conventional water pump bearing using two rows of ball rows.
FIG. 3 is an axial parallel sectional view showing a configuration example of a conventional water pump bearing using a ball row and a roller row.
[Explanation of symbols]
1 Pump shaft 11, 12 Ball raceway surface 2 Outer ring 21, 22 Ball raceway surface 3 Ball 31 Ball raceway (4-point contact type)
32 ball raceway (deep groove type)
41, 42 Cage 51, 52 Sealing seal

Claims (3)

A pump shaft in which two ball bearing inner ring raceway surfaces are formed at predetermined intervals in the axial direction on the outer peripheral surface, and two ball bearing outer ring raceway surfaces are formed on the inner peripheral surface with the above spacing therebetween. And a plurality of balls disposed in two rows of ball raceways formed between the raceways of the pump shaft and the outer race , one end of the pump shaft being an impeller and the other end being a pulley. In a water pump bearing that is engaged and used in a state where the outer ring is fixed to a water pump housing ,
A water pump bearing, wherein at least one of the two rows of ball raceways is a four-point contact type ball raceway.   2. The water pump bearing according to claim 1, wherein, among the two rows of ball raceways, the pulley-side ball raceway is a four-point contact type ball raceway. 3. The water pump bearing according to claim 2, wherein, of the two rows of ball tracks, the impeller side ball track is a deep groove type ball track.

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