A TORQUE LIMITER HAVING A DRIVE PLATE TECHNICAL FIELD

The present invention relates to torque limiters positioned between the engine and the transmission units in vehicles having internal combustion engine. PRIOR ART

Torque limiters are positioned between the engine and the transmission units in internal combustion vehicles. Torque limiters prevent the excessive torque from being transmitted to the transmission units when the torque, obtained in the engine, is over a specific value. Accordingly, a drive disc, connected to a dampening mechanism, is pressed between a pressure plate and a front cover and it controls the transmission of the torque to the front cover. In more details, the drive disc extends towards between a front cover and a rear cover. A pressure plate provided in the vicinity of the drive disc exerts pressure to the drive disc by means of a spring. In other words, the drive disc is compressed between the front cover and the pressure plate. In said embodiment, the front cover and the rear cover are formed in a manner defining a housing having a width such that the pressure plate, spring and drive disc enter in between and they are connected to each other by means of rivets. The width, formed by these parts arranged side by side, substantially affects the dimensions of the torque limiter. Moreover, due to the tight placement in this embodiment, different revisions cannot be made in the design of the torque limiter.

In the torque limiter disclosed in the application with number US3323328, the part of the drive disc which remains between the front cover and the rear cover is provided in a waved form. Thus, there remains no need to use spring and pressure plate. However, the disadvantages of the torque limiter in said embodiment are that the drive disc is difficult to produce and the load curve of the driving disc is linear and in case of abrasion, change occurs in the load and thus in the torque value.

In the torque limiter disclosed in the application with number US4274524, two driving discs are provided and they are pushed towards the friction linings together with the spring positioned in between. In this embodiment, the usage of an additional driving disc instead of the pressure plate does not provide an additional contribution. As a result, because of all of the abovementioned problems, an improvement is required in the related technical field.

BRIEF DESCRIPTION OF THE INVENTION

The present invention relates to a torque limiter, for eliminating the above mentioned disadvantages and for bringing new advantages to the related technical field.

The main object of the present invention is to provide a torque limiter of which the dimensions are reduced and the number of components is decreased.

The main object of the present invention is to provide a torque limiter of which the performance is increased. In order to realize all of the abovementioned objects and the objects which are to be deducted from the detailed description below, the present invention is a torque limiter in order to provide torque transmission in a controlled manner by means of connection to the engine from one side and connection to the transmission units from the other side in internal combustion engines, said torque limiter comprising a front cover and a rear cover for providing connection to one of the engine and transmission units, a housing defined between said front cover and said rear cover, two drive plates connected to the other one of the engine and transmission units and which partially extends into said housing, and at least one each friction linings provided between said drive plates and the front cover and the rear cover. Accordingly, at least one each middle regions are provided on one side of the drive plates and at least one each press regions are provided in order to extend into said housing and at least one each formed parts extend between said press regions and said middle regions and the formed parts extend in a different direction and in a manner forming one each pre- calculated forming angle with respect to a center axis which defines the extension direction of the middle regions, in order to form a pre-calculated angle between the press regions, and when the press regions are placed between the front cover and the rear cover, in order to obtain a secondary angle which is smaller than the forming angle; the total of thicknesses of the friction linings and two primary heights, defined between the center axis and the press region in the free form of the drive plates before the drive plates are placed into the housing, is greater than the housing height of the housing defined between the front cover and the rear cover. Thus, the press regions push the friction linings towards the front cover and towards the rear cover. In a preferred embodiment of the invention, the press regions are substantially parallel to each other.

In a preferred embodiment of the invention, the press regions are substantially parallel to the front cover and to the rear cover.

In a preferred embodiment of the invention, in the free form of the drive plates before the drive plates are placed into the housing, the sum of the two primary heights defined between the center axis and the press region and the thicknesses of the friction linings is substantially greater than the housing height of the housing defined between the front cover and the rear cover.

In a preferred embodiment of the invention, at least one radially outward formed external region is provided as the extension of the press region; the press region extends in a different direction in order to form a pre-calculated angle between the external regions and the press regions; and said angle increases when the press regions are placed between the front cover and the rear cover.

In a preferred embodiment of the invention, the external region is provided in an interrupted manner along the external periphery of the press region.

In a preferred embodiment of the invention, at least one press spring is provided which is positioned between the press regions and which pushes the press regions towards the front cover and towards the rear cover.

BRIEF DESCRIPTION OF THE FIGURES

In Figure 1 a, a representative frontal view of the subject matter torque limiter is given. In Figure 1 b, a representative cross sectional view of the subject matter torque limiter is given.

In Figure 2a, a representative isometric view of the drive plate of the subject matter torque limiter is given.

In Figure 2b, a representative cross sectional view of the drive plate of the subject matter torque limiter is given. In Figure 3a, a representative view of the combination form of the drive plates of the subject matter torque limiter is given. In Figure 3b, a representative view after approaching the press regions of the drive plates of the subject matter torque limiter to each other is given.

In Figure 4, a representative cross sectional view of an alternative embodiment of the subject matter torque limiter is given.

In Figure 5, a representative cross sectional view of an alternative embodiment of the subject matter torque limiter is given.

In Figure 6, a representative isometric view of the alternative embodiment of the drive plate of the subject matter torque limiter is given.

REFERENCE NUMBERS

10 Torque limiter

1 1 Hub

12 Dampening mechanism

13 Cover Part

131 Front cover

132 Rear cover

133 Housing

14 Friction lining

15 Press spring

20 Drive plate

21 Middle region

22 Formed part

23 Press region

24 External region L Housing width

a Center axis

a Forming angle a' Secondary angle

hi Primary height

h2 Secondary height DETAILED DESCRIPTION OF THE INVENTION

In this detailed description, the subject matter torque limiter (10) is explained with references to examples without forming any restrictive effect only in order to make the subject more understandable.

As can be seen in Figure 1 a and 1 b, the subject matter torque limiter (10) has a hub (1 1 ) connected to the engine, a cover part (13) connected to the transmission units and a dampening mechanism (12) provided between the cover part (13) and the hub (1 1 ). The connection of the dampening mechanism (12) to the cover part is provided by means of drive plates (20).

In more details, said cover part (13) comprises a front cover (131 ) and a rear cover (132). Said front cover (131 ) and said rear cover (132) are preferably provided in the form of hollow circular plates. The front cover (131 ) and the rear cover (132) are fixed to each other from the vicinity of the outer walls thereof. In the preferred embodiment, the fixation process is realized by means of rivets. The front cover (131 ) and the rear cover (132) are formed from the sides facing the centers thereof such that there is a pre-calculated distance between said covers (131 , 132). In other words, a housing (133) is formed between the front cover (131 ) and the rear cover (132). The distance between the front cover (131 ) and the rear cover (132) is defined as a housing width (L).

The drive plates (20) extending from the dampening mechanism (12) towards the cover part (13) at least partially enters into said housing (133). Moreover, inside said housing (133), there are the friction linings (14) and the drive plates (20) provided between the rear cover (132) and the front cover (131 ).

In the subject matter torque limiter (10), two drive plates (20) are provided which are at least partially parallel to each other. Accordingly, while the parts of the drive plates (20) existing on the dampening mechanism (12) side are provided in a connected manner to each other, the parts which enter into the housing (133) are formed such that there is a pre-calculated distance in between. With reference to Figure 1 b, 2a and 2b, the drive plate (20) has an middle region (21 ) provided on the side thereof facing the dampening mechanism (12), a press region (23) extending inside the housing (133) and at least one formed part (22) extending between the press region (23) and the middle region (21 ).

As will be seen in Figure 3a, the formed parts (22) extend in a manner creating a pre- calculated forming angle (a) with respect to the middle region (21 ). By means of this, the drive plates (20) show resistance like a spring against the forces exerted onto the press regions (23). In other words, the drive plates (20) are connected to each other through the middle regions (21 ) and the formed parts extend in different directions. Thus, a pre- calculated primary height (hi ) is obtained between the press region (23)and a center axis (a) defined at the extension direction of the middle region (21 ). In the preferred embodiment of the present invention, there are formed parts (22) in both drive plates (20) and the primary heights (hi ) are provided in an equal manner to each other. In alternative embodiments, the primary height (hi ) of one of the drive plates (20) can be smaller than the primary height (hi ) of another drive plate or one of the drive plates (20) can be embodied in a flat manner. The two drive plates (20) are at least partially connected to each other through the middle regions (21 ) thereof. Thus, a distance is obtained which is equal to the sum of the primary heights (hi ) formed at the two drive plates (20) between the press regions (23). Moreover, the sum of the friction lining (14) thicknesses and the primary heights (hi ) is provided in a greater manner than the housing height (L).

As will be seen in Figure 3b, in order to place the friction linings (14) and the drive plates (20) into the housing, a force is exerted in a manner approaching the press regions (23) to each other. By means of this, the forming angle (a), defined between the center axis (a) and the formed parts (22), is narrowed and a secondary angle (α') is obtained. In other words, the distance between the press region (23) and the center axis (a) is reduced and it is brought into a secondary height (h2). Thus, when the friction linings (14) and the press regions (23) are placed into the housing (133), the press regions (23) push the friction linings (14) towards the front cover (131 ) and towards the rear cover (132). By means of this, the drive plates (20) automatically exert pressure to the friction linings (14) along the surfaces thereof which are in contact with the press regions (23). Thus, a force is formed which is exerted along the contact surfaces instead of pressure force transferred to the drive plates (20) by the pressure spring by means of linear contact in the prior art, and a more effective friction is obtained. Moreover, without using pressure plates used in the prior art, the friction linings (14) are compressed between the front cover (131 ) and the rear cover (121 ) and the drive plates (20).

As will be seen in Figure 5, in an alternative embodiment of the present invention, a formed external region (24) is provided at the external part in the radial direction of the press region (23) of the drive plates (20). The end of this formed external region (24) contacts the adjacent drive plate. Thus, since force is exerted from the formed part (22) and from the external region (24) to the friction lining (14), force distribution on the press region (23) is more uniform.

As can be seen in Figure 6, in the preferred alternative embodiment of the present invention, the described external region (24) is formed in an interrupted manner along the periphery of the drive plate (20). The connection of the friction lining (14) to the press region (23) is realized by means of riveting through the parts where the external region (24) does not exist. Thus, a greater contact surface is provided for the friction lining (14) and the press region (23). The assembly of this embodiment is realized in a similar manner to the above mentioned description.

In an alternative embodiment of the present invention, at least one press spring (15) is positioned between the press regions (23) of the drive plates (20). Thanks to said embodiment, the thicknesses of the drive plates (20), which will be used, can be reduced. In other words, thanks to the press spring (15) positioned between the press regions (23), the thicknesses of the drive plates (20) can be reduced. By means of this, the thickness of the torque limiter (10) is reduced.

In a possible embodiment of the present invention, the friction linings (14) are adhered to the drive plates (20). In this embodiment, friction occurs between the friction linings (14) and the front cover (131 ) and the rear cover (132). In this friction region which occurs, the front cover (131 ) and the rear cover (132) are made of stainless steel material in order to decrease corrosion. In an alternative embodiment of the present invention, the friction linings (14) are adhered to the front cover (131 ) and to the rear cover (132). In this embodiment, friction occurs between the friction linings (14) and the drive plates (20). In order to prevent corrosion in this friction region, the drive plates (20) are made of stainless steel material. Thus, less stainless steel material is used when compared with the other embodiment and the cost is reduced.

The protection scope of the present invention is set forth in the annexed Claims and cannot be restricted to the illustrative disclosures given above, under the detailed description. It is because a person skilled in the relevant art can obviously produce similar embodiments under the light of the foregoing disclosures, without departing from the main principles of the present invention.