KR20140097416A - Torque limiter - Google Patents

Abstract

A torque limiter (1) of the present invention comprises a flexible flywheel (3) fixed to a drive shaft, a first pressure plate (13) fixed to the flywheel (3) And a friction element 17 inserted between the first pressure plate 13 and the second pressure plate 19 and adapted to drive the driven shaft. The second pressure plate 19 is fixed to the casting flywheel 3 in the rotating direction, And elastic means (22) capable of applying an axial force to said second pressure plate (19) to grip said friction element (17) between said first pressure plate (13) and said second pressure plate Type. The elastic means (22) is inserted between the flexible flywheel (3) and the second pressure plate (19).

Description

Torque limiter {TORQUE LIMITER}

The present invention relates to a torque limiter.

The prior art provides details of a torque limiter that is intended to be inserted between a drive shaft and a driven shaft. This type of limiter may be used in particular in a vehicle and may cause the torque to be transmitted to an inseparable transmission system, such as an automatic transmission system or a continuously variable transmission system (often referred to as "CVT"), for example by means of an internal combustion engine.

Conventionally, such a torque limiter has a friction element held between two pressure plates under the action of an elastic force, and the gripping effect is such that when the torque applied by the drive shaft exceeds a predetermined limit value, So that the excess torque applied by the drive shaft is distributed through the frictional effect so as to protect the components located below the driven shaft from any damage.

In other words, the torque limiter functions as a kind of fuse between the drive shaft and the driven shaft.

One particular type of torque limiter is a type with a flexible flywheel. The presence of a flexible flywheel may cause axial movement by the drive shaft and any impact transmitted during the nutation to be absorbed, particularly when the drive shaft is driven by a combustion engine.

It is an object of the present invention to propose a relatively straight-line structure for the torque limiter so as to reduce manufacturing costs and space required.

The above object of the present invention can be achieved by a hydraulic control apparatus for a motorcycle including a flexible flywheel fixed to a drive shaft, a first pressure plate fixed to the flywheel, a second pressure plate movable in the axial direction but fixed in the rotational direction with respect to the flexible flywheel A friction element inserted between the first pressure plate and the second pressure plate to drive the driven shaft and an axial force is applied to the second pressure plate to grip the friction element between the first pressure plate and the second pressure plate And a limiter in which the elastic means is inserted between the flexible flywheel and the second pressure plate.

Since the resilient means are attached to the flexible flywheel, it is possible to obviate the need for the entire series of intermediate components that have hitherto made the manufacture of torque limiters with flexible flywheels complicated, in particular increasing the fastening space in the axial direction .

This structure means that the torque limiter can be manufactured with a minimum number of components, resulting in more economical manufacture and less installation volume.

According to another optional feature of the torque limiter according to the invention,

The resilient means comprises a resilient washer of tabular shape which is fitted with a pre-stress between the flexible flywheel and the second pressure plate;

The second pressure plate has an axial thickness substantially greater than the first pressure plate;

The first pressure plate is in the form of a cover of the torque limiter;

The torque limiter also having means for attenuating acyclics, the input of the damping means acting in conjunction with the friction element, the output of the damping means being operable in conjunction with the driven shaft have;

The torque limiter has a plate coupled to the flexible flywheel to disperse stress imparted by the mounting means of the flexible flywheel to the drive shaft;

The torque limiter comprises fixed mounting means for mounting a flexible flywheel on the drive shaft and an orifice for providing access to the mounting means;

The orifice traverses the damping means;

The first pressure plate and the second pressure plate are connected by a plurality of taps to cause the two pressure plates to move axially relative to each other and to prevent any rotational movement of the two pressure plates relative to each other.

Other features and advantages of the present invention will become apparent from a consideration of the accompanying drawings.

1 is a front view of a torque limiter according to the present invention,
Fig. 2 is a sectional view along line II-II in Fig. 1 of a torque limiter according to the present invention when assembled on a crankshaft and disposed inside a stationary housing; Fig.
3 is a partial view of a torque limiter in accordance with the present invention along arrow III in Fig.

1 and 2, the torque limiter 1 according to the present invention includes a metal plate 3 in the form of a flexible flywheel adapted to be mounted on a drive shaft 5, such as a crankshaft of an internal combustion engine, Respectively.

Mounting means 7i such as a hollow head screw is used to fix the flexible flywheel 3 on the crankshaft 5.

Preferably, the step of doubling the flexible flywheel 3 by using the stress distribution plate 9 in the mounting region of the crankshaft 5 may be taken.

On the flexible flywheel 3, a rigid cover 11 having an annular portion 13 constituting a first pressure plate is mounted.

The lining (15) of the friction element (17) is arranged on the opposite side of the first pressure plate.

On the other side of this lining 15 is a second pressure plate 19 which is preferably of a generally annular shape and whose axial thickness is larger than that of the first pressure plate 13.

The second pressure plate 19 is fixed in the rotational direction with respect to the cover 11 and the flexible flywheel 3 and can be moved axially with respect to these two elements. As such, a free but rotationally closed motion in the axial direction is achieved by a plurality of elastic tabs 21a, 21b, 21c uniformly distributed around the limiter (see FIGS. 1 and 3).

Between the flexible flywheel 3 and the second pressure plate 19 there is a Belleville type elastic washer 22 centered on the second pressure plate or flexible flywheel 3.

This resilient washer 22 has a first pressure plate 19 and a second pressure plate 19 for the flywheel 3 to partially reduce the stress level and secondly to improve the support for both the second pressure plate and the flywheel, A bevel, a groove or an embedment on the outer and inner diameters.

This resilient washer is subjected to permanent stresses on the second pressure plate 19 so that the lining 15 of the friction element 17 is firmly gripped between the second pressure plate and the first pressure plate 13 .

Although not shown here, in a further variant, the friction element 17 can be connected directly to the driven shaft, which can drive, for example, an automatic transmission system or a continuously variable transmission system.

In the variant shown, the torque limiter according to the invention comprises means for attenuating any non-periodic vibrations transmitted by the crankshaft 5, as is already known.

This damping means is provided with two guide washers 23 and 25 and an attenuating disc 27 which is itself attached to a boss 29 capable of driving a driven shaft (not shown) is arranged between these guide washers .

A plurality of springs or a group of springs 31a to 31d acting together with the damping disk 27 are arranged between the two guide washers 23 and 25.

The guide washer 25 itself is connected to the friction element 17.

The two guide washers 23 and 25 and the disc 27 are provided with an orifice 33i which provides access for the screwing tool for the mounting means 7i.

Advantageously, the head 35i of the mounting means 7i is too large to pass through the orifice 33i so that the mounting means 7i can be considered to be fixed inside the torque limiter according to the invention Points should be kept in mind.

The damping means includes a single or multiple history (variable history) system, as is already known.

This system has in particular a recess Ei and a friction washer 36 with a stud Ti uniformly spaced around its periphery.

The stud Ti may allow the friction washer 36 to engage the guide washer 25.

The arrangement of the recess Ei and the stud Ti is such that the orifice 33i, which allows the threading tool to pass, is not blocked.

As is known per se, torque limiter 1 is disposed in protective housing 37 and then placed in place between the internal combustion engine and an automatic transmission system or a continuously variable transmission system (not shown).

The operating method and advantages of the torque limiter according to the invention are derived directly from the above description.

The crankshaft 5, the flexible flywheel 3, the cover 11, the first pressure plate 13, the second pressure plate 19 and the elastic washer 22 are permanently rotated as a single unit.

The lining 15 of the friction element 17 is between the first pressure plate 13 and the second pressure plate 19 as long as the torque transmitted by the crankshaft 5 is lower than the predetermined value forced by adjustment of the elastic washer Will continue to be gripped.

When the torque transmitted by the crankshaft 5 exceeds a predetermined value the lining 15 of the friction element 17 is displaced by the first pressure plate 13 and the second pressure plate 19 so that part of the torque is dispersed by friction, , The torque to be transmitted to the driven shaft can be limited and any subsequent components driven by the driven shaft can be prevented from being damaged.

The damping means comprising two guide washers 23 and 25, an attenuating disc 27 and a plurality of springs 31a through 31d allows the periodic vibration transmitted by the crankshaft 5 to be absorbed.

It should be noted that the flexible flywheel 3 allows any impact transmitted by the crankshaft 5 in the axial or frontal direction of motion.

The fact that the second pressure plate 19 also provides a relatively high axial thickness allows the second pressure plate to act as an inertial flywheel so that heat generated as a result of friction between the lining 15 and the friction element 17 It should be noted that it helps to disperse.

If the inertia requirement is low, a thin pressure plate can alternatively be employed. This pressure plate is made of steel and can be manufactured by press cutting.

It should also be noted that the firm attachment of the mounting means 7i to the torque limiter means that the torque limiter can be carried without risk of losing the mounting means.

The presence of the orifice 33i allows the mounting means to be actuated to reliably act with the crankshaft 5 despite the mounting means being firmly attached.

As a result of these features, the torque limiter according to the invention can be preassembled as a whole before being mounted on the crankshaft 5. This modular design greatly facilitates the integration of torque limiters during the manufacturing process.

In order to remove the torque limiter from the crankshaft 5 it may be necessary to pivot the friction element 17 and its associated damping components such that the orifice 33i is in a position facing the mounting means 7i . This can be done by using a channel-like tool that can be inserted into the boss 29.

This is unavoidable when the cover 11 is attached to the flexible flywheel 3 immovably (e.g., by rivets).

On the other hand, when this cover is attached to the flexible flywheel in a detachable manner by a bolt / nut or the like as shown in the figure, the approach to the mounting means 7i is obtained by removing the cover 11 of the flexible flywheel 3 Can be.

It should also be noted that because the orifice 33i is smaller than the head 35i of the mounting means 7i it is possible to increase the mechanical stability by being able to limit the size of the area without any damping material 27 .

The fact that the elastic washer 22 is inserted without any additional intermediate elements between the flexible flywheel 3 and the second pressure plate 19 is a very simple and less expensive construction, it means.

Until now, such a structure has not been envisioned, since it was mistakenly believed that the elastic washer 22 could not be placed directly on a component having certain flexibility, such as the flexible flywheel 3.

It is clear that the invention is not limited to the embodiments described above, and that the title of the invention is purely illustrative and not restrictive.

In this way, for example, the resilient washer 22 can be replaced with a cutout (e.g., in the form of a tab) formed directly on the flexible flywheel.

This can eliminate the need for the elastic washer 22, resulting in additional savings of one part.

Claims (12)

In the torque limiter 1,
A first pressure plate (13) fixed to the flywheel (3), and a second pressure plate (13) fixed to the drive shaft, the first pressure plate (13) being movable relative to the flexible flywheel A friction element 17 inserted between the first pressure plate 13 and the second pressure plate 19 and adapted to drive the driven shaft; (22) capable of exerting an axial force on the second pressure plate (19) so as to grip between the first pressure plate (13) and the second pressure plate (19), and the flexible flywheel And a limiter in which the elastic means (22) is inserted between the second pressure plates (19)
The first pressure plate 13 and the second pressure plate 19 are connected by a series of tabs 21a to 21c to cause these two pressure plates to move in the axial direction with respect to each other and to cause these two pressure plates To prevent rotation
Torque limiter. The method according to claim 1,
The elastic means includes a Belleville type elastic washer 22 disposed in a state of being pre-stressed between the flexible flywheel 3 and the second pressure plate 19
Torque limiter. The method according to claim 1,
The elastic means is inserted between the flexible flywheel 3 and the second pressure plate 19 without any additional intermediate components
Torque limiter. The method according to claim 1,
Said resilient means being provided by a cut-away portion disposed in said flexible flywheel
Torque limiter. 5. The method according to any one of claims 1 to 4,
The second pressure plate 19 has an axial thickness that is thicker than the thickness of the first pressure plate 13
Torque limiter. 5. The method according to any one of claims 1 to 4,
The second pressure plate 19 is made of a thin steel
Torque limiter. 5. The method according to any one of claims 1 to 4,
The first pressure plate 13 is in the form of a cover 11 of the torque limiter 1
Torque limiter. 5. The method according to any one of claims 1 to 4,
Further comprising means (23, 25, 27 and 31a-31d) for attenuating non-periodic vibrations, the input of said damping means acting in conjunction with said friction element (17) That can operate in conjunction with
Torque limiter. 5. The method according to any one of claims 1 to 4,
And a plate (9) attached to the flexible flywheel (3) to disperse stresses of the mounting device of the flexible flywheel (3) relative to the drive shaft
Torque limiter. 5. The method according to any one of claims 1 to 4,
Further comprising mounting means (7i) for fixing said flexible flywheel (3) on said drive shaft and an orifice (33i) for providing access to said mounting means
Torque limiter. 9. The method of claim 8,
(7i) for fixing said flexible flywheel (3) on said drive shaft and an orifice (33i) for providing access to said mounting means,
The orifice (33i) passes through the damping means (23, 25, 27)
Torque limiter. 12. The method of claim 11,
The damping means comprises at least one friction washer (36) having a recess (Ei) and a mounting stud (Ti) arranged so as not to block the orifice (33i)
Torque limiter.

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