JPH066763U - Torque limiter with automatic return function - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention is a torque limiter in which a cage and an inner ring are brought into rolling contact with each other by rolling elements, and creep is generated between them to automatically restore the rolling element to the cage and the inner ring. Eliminates the need for special processing for assembly and reduces the manufacturing process. A cylindrical surface 5 is formed on the inner ring 1, a cam surface 9 made up of a polygonal leaf spring 8 is formed on the outer ring 2, and a roller 13 for engagement is incorporated in a cage 14 provided between the inner and outer rings. Cylindrical rollers 22 are provided between the inner ring 1 and the annular member 16 that is connected to the cage 14.
Is press-fitted, and by the press-fitting, the annular member 16 and the annular portion 19 of the outer ring 2 are brought into contact with each other, and the rolling motion of both of them causes the cage 14 to rotate at a low speed to generate creep.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a torque limiter having a function of automatically returning.

[0002]

[Prior art]

 In propeller propulsion equipment of small ships and hydraulic circuits of refrigerator compressors, etc., when the driven side recovers to the normal state by disconnecting the power transmission on the driven side against the overload on the driven side, the original state is automatically restored. A torque limiter that returns to and repeats torque transmission is required.

Further, in the above torque limiter, if the automatic return is repeated at an extremely short time interval while the prime mover side is rotating at a high speed, the follower side is forced to force a predetermined long time. A function that automatically returns at a time interval is required.

Conventionally, as a torque limiter that automatically returns at such a long interval, there is a torque limiter previously proposed by the applicant in Japanese Patent Application No. 4-111281.

In this proposal, as shown in FIG. 6, a cylindrical surface 5 and a cam surface 9 composed of a polygonal leaf spring 8 are formed on the surfaces of the inner ring 1 and the outer ring 2 that face each other. The roller 13 that engages with the minimum clearance between the cylindrical surface 5 and the cam surface 9 is incorporated in the pocket of the cage 14 provided between the two.

Further, the retainer 14 and the outer ring 2 are provided with annular portions 30, 31 which are fitted with a clearance respectively, a ball bearing 32 is incorporated between the inner ring 1 and the retainer 14, and the ball 33 of the ball bearing 32 is incorporated. By press-fitting the holder 14, the cage 14 is rolled and guided, and the annular portion 30 is radially deformed so that the annular portions 30 and 31 are brought into contact with each other at a plurality of positions.

In the structure described above, when the leaf spring 8 forming the cam surface 9 is deformed and the roller 13 passes through the engaging position, the cage 14 is rotated by the inner ring 1 via the ball 33 to rotate the outer ring 2 The rolling motion is performed on the circular ring portion 31 to cause creep, and the roller 13 is moved to the next engagement position at a low speed.

[0008]

[Problems to be solved by the device]

 By the way, as described above, in the structure in which the ball bearing 32 is press-fitted between the inner ring 1 and the cage 14 and the cage 14 is rolled and guided, the ball is provided on the outer diameter surface of the inner ring 1 and the inner diameter surface of the cage 14. It is necessary to provide circumferential grooves 34 and 35 for guiding the balls 33 of the bearing 32. However, such circumferential grooves 34 and 35 have a problem that the number of manufacturing steps of the inner ring and the cage is increased and the manufacturing cost is increased.

Further, in the ball bearing 32, it is necessary to press-fit and assemble the ball 33 into the ball retainer 36, and in addition, it is necessary to press-fit the ball 33 accurately to the positions of the circumferential grooves 34 and 35. Therefore, there is a problem that it takes time and effort to assemble and the work cost increases.

Therefore, an object of the present invention is to provide a torque limiter capable of reducing the manufacturing process and cost by changing the shape of rolling elements that generate creep.

[0011]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention provides a cage which is formed between a cylindrical surface and a polygonal cam surface on opposite surfaces of a bearing ring fitted inside and outside, and which is incorporated between both the bearing rings. The pocket is provided with an engaging element that engages with the minimum clearance of the cylindrical surface and the cam surface, and the surface of the minimum clearance of the cam surface is made of an elastic material. An annular part that fits with a clearance is provided, and between the annular part of the cage and the bearing ring on the drive side, press fit a plurality of cylindrical rollers that guide the cage, and hold the cylindrical rollers by press fitting. The deformation amount of the container was set to be larger than the fitting gap between the two annular parts.

[0012]

[Action]

 When the cylindrical roller is used as described above, since the cylindrical roller itself has a function of guiding the rolling raceway, it is not necessary to provide a circumferential groove for guiding the race ring or the cage. Moreover, since it is not necessary to accurately determine the position of the press fit to the bearing ring and the annular portion, the assembly can be performed easily.

[0013]

【Example】

 1 to 3 show a torque limiter of the embodiment. As shown in FIGS. 1 and 2, one end of the inner ring 1 and the outer ring 2 are rotatably supported by the bearing 3 and the engaging member 18, and the other end is rotatably supported by the bearing 4 and the bearing housing 25. It is held coaxially by the guide of No. 4.

The outer diameter surface of the central portion of the inner ring 1 is formed by a cylindrical surface 5, and the inner diameter surface 6 of the outer ring 2 facing the cylindrical surface 5 is provided with eight notches 7 at equal intervals in the circumferential direction. Each of the notches 7 is formed with a leaf spring 8 having a substantially octagonal ring shape.

The leaf spring 8 is formed of spring leafs 8 a that are divided into eight equal parts, and the inner surface of each spring leaf 8 a forms a wedge-shaped space with the cylindrical surface 5 of the inner ring 1. Forming surface 9. Further, the spring plates 8a are assembled with a slight interference fit between the notches 7 of the outer ring 2, and the spring plates 8a are provided between the spring plates 8a and the inner diameter surface 6 of the outer ring 2. Is provided to allow the deformation of the. Further, a protrusion 11 directed to the cylindrical surface 5 of the inner ring 1 is formed in the center of the leaf spring 8, and the dimension a of the minimum clearance 12 between the protrusion 11 and the cylindrical surface 5 is the diameter of the roller 13 described later. It is set smaller than d.

A retainer 14 is provided between the leaf spring 8 and the cylindrical surface 5, and a large number of pockets 15 are provided on the peripheral surface of the retainer 14 at equal intervals corresponding to the cam surface 9. A roller 13 as an engaging element is incorporated in each of the pockets 15.

The roller 13 is formed so that the outer diameter dimension d is smaller than the gap other than the minimum clearance 12 between the cam surface 9 and the cylindrical surface 5, and as shown in FIG. It is adapted to engage the cam surface 9 and the cylindrical surface 5 only at the side. Further, the outer diameter dimension d of the roller 13 is set to be smaller than the distance between the leaf spring 8 and the cylindrical surface 5 when the square ring-shaped leaf spring 8 is bent toward the recess 7 side. It is ready to pass.

Further, the tip of the cage 14 projects toward the bearing 3 side, and an annular member 16 coaxial with the inner and outer rings is connected to the projecting portion 14a. The annular member 16 is tightly fitted to the cage 14 by fitting the inner diameter surface and the uneven portion 17 provided on the outer diameter surface of the protruding portion 14a, and by fitting the annular member 16 to the annular member 16. The cage 14 is immovable in the axial direction, but is connected so as to be relatively rotatable with a predetermined torque in the rotational direction.

An engaging member 18 having an L-shaped cross section is integrally press-fitted at the tip of the outer ring 2, and the engaging member 18 is fitted into the annular member 16 to form an annular ring. The part 19 is formed.

The annular member 16 and the annular portion 19 are fitted with each other through a slight clearance δ, and the fitted clearance δ is defined by the inner diameter of the annular member 16 and the outer diameter of the annular portion 19. Nominal size of dimension It is set to a value less than a few hundredths of the dimension D.

On the other hand, a cylindrical roller bearing 20 is incorporated between the annular member 16 and the cylindrical surface 5 of the inner ring 1 as shown in FIGS. The cylindrical roller bearing 20 comprises an annular roller cage 21 and three cylindrical rollers 22 arranged by the roller cage 21 at intervals of 120 degrees in the circumferential direction. The cage 14 is rotationally guided with respect to the inner ring 1.

Further, the diameter D of the cylindrical roller 22 is larger than the distance between the annular member 16 and the inner ring 1, so that each cylindrical roller 22 is assembled between the annular member 16 and the inner ring in a press-fitted state. The press-fitting of the cylindrical roller causes the annular member 16 to deform with the cylindrical roller 22 as an apex as shown in FIG. 3, and the deformed portion 23 causes the annular member 16 to move to the annular portion of the outer ring 2. 19 is in point or line contact.

Further, the pocket 24 of the roller cage 21 for accommodating the cylindrical roller 22 is formed in a cylindrical shape toward the axial direction, and by inserting the cylindrical roller 22 in the axial direction of the cage 14, the pocket 24 is formed. It is formed so that it can be incorporated.

The torque limiter of this embodiment has the above-mentioned structure, and the inner ring 1 is connected to the prime mover side and the outer ring 2 is connected to the driven side. As shown in FIG. When the outer ring 2 is fixed while the roller 13 is in contact with the cam surface 9 of the ring-shaped leaf spring 8 and the inner ring 1 is rotated in the direction of the arrow, the roller 13 is engaged with the cylindrical surface 5 and the cam surface 9 and the clutch And the outer ring 2 rotates together with the inner ring 1.

From this state, when the torque applied to the outer ring 2 becomes large, as shown in FIG. 4, the cam surface 9 of the spring 8 constituting the clutch bends toward the recess 7 side to continue the torque transmission. When the torque exceeds a certain value, the roller 13 passes through the minimum clearance portion 12 and is released to the side opposite to the cam surface 9 that has been acting as a clutch, and the clutch function is lost.

When the prime mover side continues to rotate with the torque transmission being released and the inner ring 1 and the outer ring 2 rotate relative to each other, the rotational load of the inner ring 1 is transmitted to the annular member 16 via the cylindrical rollers 22. Therefore, the annular member 16 makes an inward rolling motion around the outer diameter of the annular portion 19 of the outer ring 2 to cause creep. That is, when the cylindrical roller 22 goes around the inside of the annular member 16, the annular member 16 and the annular portion 19 relatively rotate by an amount πδ obtained by multiplying the fitting clearance δ by the pi. In this case, since the value of the fitting clearance δ is set to a small value as described above, the cage 14 rotates at a lower speed than the rotation of the inner ring 1, and the roller 13 is rotated by a small distance per rotation. To move. Therefore, after the driven side has stopped due to an abnormal condition, the roller 13 does not reach the next engagement position after a long time, and the automatic return with a sufficient time margin can be repeated.

In the above embodiment, the inner ring 1 is on the driving side and the outer ring 2 is on the driven side. Conversely, even if the outer ring 2 is on the driving side and the inner ring 1 is on the driven side, the same operation as described above is achieved. Obtainable. Further, two or four or more cylindrical rollers 22 may be incorporated at equal intervals.

[0028]

【effect】

 As described above, in the present invention, the cylindrical rollers are press-fitted between the bearing ring and the cage, so that it is not necessary to provide a circumferential groove for guiding the bearing ring or the cage, and the manufacturing process is reduced. Therefore, the cost can be reduced.

Further, since the cylindrical roller does not need to be forcibly fitted into the pocket of the roller cage and is not required to be press-fitted to the bearing ring and the cage in the correct position, the workability of assembling is greatly improved. There are advantages.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing a torque limiter of an embodiment.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a perspective view showing a cylindrical roller bearing.

FIG. 5 is an enlarged sectional view showing a clutch portion of the above.

FIG. 6 is a vertical sectional front view showing a conventional example.

[Explanation of symbols]

 1 Inner ring 2 Outer ring 5 Cylindrical surface 8 Leaf spring 9 Cam surface 13 Roller 14 Cage 16 Ring member 19 Ring part 20 Cylindrical roller 21 Roller cage 22 Cylindrical roller

Claims (1)

[Scope of utility model registration request] 1. The surface of the bearing ring that fits inside and outside,
A cylindrical surface and a polygonal cam surface are formed, and an engaging element that engages with the minimum clearance between the cylindrical surface and the cam surface is provided in the pocket of the retainer that is installed between the two bearing rings. The surface of the minimum clearance of the surface is made of an elastic material, and an annular portion that fits in the driven side bearing ring and the cage with a gap is provided, and the annular portion of the cage and the drive side bearing ring are In between, press-in a plurality of cylindrical rollers that guide the cage,
A torque limiter with an automatic return function in which the amount of deformation of the cage due to the press-fitting of the cylindrical rollers is set to be larger than the fitting gap of the both annular portions.