A TRACTOR CLUTCH HAVING ADJUSTABLE LEVER EMBODIMENT TECHNICAL FIELD

The present invention relates to a tractor clutch embodiment having an adjustable lever developed for providing adjustment of the clutch plate separation amount and of the clutch pedal load particularly in tractor clutch systems.

PRIOR ART

Clutch systems are used for engaging torque transmission units and the engine in vehicles or for disengaging the present connection. Clutch system connects the engine flywheel and the input shaft of the gearbox and disengages this connection by means of pressing the clutch pedal. Clutch pedal is operated by means of a pedal load and said pedal load is determined during the design of the clutch system. The press load, which is provided by the pre- tensioned compression spring which is positioned between the pressure plate and the fixed arm, is transferred to the pedal by means of a lever. Thus, a pedal load depending on the press load is obtained. The value of the pedal load depends on the adjustable lever proportion of the adjustable lever.

The pedal load is going to remain when a standard pressure plate and a standard adjustable lever are used. Thus, changing of the pedal load requires changing of these components. This condition disables production by means of the same components in case there are particularly different customer requests. Changing of these components presents product variety for obtaining different pedal loads and separate lifting and bearing loads shall be adjusted according to each product used by means of changing. Within this context, the extra labor durations, which occur in case the product variety is widened and in case different components are used in production, lead to increase in the total production costs.

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 tractor clutches, 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 tractor clutch having a standardized adjustable lever which does not need changing for different pedal loads.

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 clutch for tractor comprising an adjustable lever comprising an elbow arm provided on a cover of the clutch by means of a cover connection pin and a fixed arm positioned by means of a support pin positioned on the elbow arm and defining a support point on said elbow arm. Accordingly, said clutch comprises an adjustment screw provided in the elbow arm and said adjustment screw guides the support pin as to provide a movement of said support point between a backward adjustment position and a forward adjustment position with respect to the cover connection pin in order to obtain changeable pedal load according to different adjustable lever proportions through a press load which acts on the fixed arm. This clutch according to the invention has the advantage of changing pedal load without redesigning any component of adjustable lever. In order to accomplish this change, a distance between fixed arm and support point is changed thanks to adjustment screw. The rotation of the adjustment screw relative to the elbow arm causes change of the distance. So that, pedal load and lift amount of the pressure plate can be adjusted easily and quickly. Thanks to the invention, one adaptable clutch could be used instead of several different clutches without engaging new technical or financial investments.

The invention can exhibit one or another of the characteristics described below, combined with one another or taken independently of one another.

In a preferred embodiment of the present invention, the clutch comprises a cover having a body portion in circular form around an axis Y and a pressure plate connected to the cover by using the adjustable lever. In a preferred embodiment of the present invention, a screw adjustment pin is provided at the elbow arm in a manner connected to the adjustment screw and providing linear movement of the support pin by means of the circular rotational movement of said adjustment screw. In a preferred embodiment of the present invention, the adjustable lever comprises a screw adjustment pin connected to the adjustment screw by screw connection provided onto the elbow arm in a manner to provide linear movement of the support pin by means of the circular rotational movement of said adjustment screw.

In another preferred embodiment of the present invention, a casing is attached onto the adjustment screw and connected to the support pin in a manner of transmitting the movement of said adjustment screw.

In another preferred embodiment of the present invention, a casing is provided where the support pin is connected in a manner transmitting the movement of said adjustment screw.

In another preferred embodiment of the present invention, said casing comprises a base where the adjustment screw is connected and flaps embodied mutually at the continuation of said base and where the support pin is placed.

In another preferred embodiment of the present invention, a movable arm is provided which is connected at the support point between said fixed arm and said elbow arm.

In another preferred embodiment of the present invention, a support hole is provided at one end of said movable arm and where the support pin is placed, a lower support hole is placed at the other end of the movable arm and a lower support pin positioned in said lower support hole.

In another preferred embodiment of the present invention, an adjustment hole, wherein the support pin is guided, is provided on the elbow arm. For example, the adjustment hole has an oblong shape. In another preferred embodiment of the present invention, the minimum value of the pedal load is provided at the backward adjustment position of the support point obtained by means of the most forward position of the adjustment screw.

In another preferred embodiment of the present invention, the minimum value of the pedal load is provided at the backward adjustment position of the support point obtained by screwing the adjustment screw in a manner to move radially the adjustment screw in the opposite direction of the axis Y. In another preferred embodiment of the present invention, the maximum value of the pedal load is provided at the forward adjustment position of the support point obtained by means of the most backward position of the adjustment screw.

In another preferred embodiment of the present invention, the maximum value of the pedal load is provided at the forward adjustment position of the support point obtained by screwing the adjustment screw in a manner to move radially the adjustment screw in the direction of the axis Y.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is the general assembly view of the adjustable lever connected to the tractor clutch.

Figure 2 is the cross sectional view of the adjustable lever.

Figure 3 is the exploded view of the adjustable lever. Figure 4 is the comparative view of the adjustable lever related to three different adjustment positions.

REFERENCE NUMBERS 10 Adjustable lever

20 Elbow Arm

21 Carrier Sheet

21 1 Sheet Connection Hole

212 Screw Connection Hole

213 Adjustment Hole

214 Cover Connection Hole

22 Sheet Connection Pin

23 Contact Part

24 Screw Adjustment Pin

25 Adjustment Screw

26 Casing

261 Base 262 Flap

263 Pin Hole

27 Cover Connection Pin

30 Movable Arm

31 Support Hole

32 Lower Support Hole

33 Support Pin

34 Lower Support Pin

40 Fixed Arm

41 Pin Housing

50 Clutch

51 Cover

52 Plate

53 Spring

A: Backward Adjustment Position

B: Middle Adjustment Position

C: Forward Adjustment Position

M: Support Point

X: Support Point Horizontal Distance

Y: Support Point Orthogonal Distance

X1 : Backward Position Horizontal Distance

X2: Middle Position Horizontal Distance

X3: Forward Position Horizontal Distance

Y1 : Backward Position Orthogonal Distance

Y2: Middle Position Orthogonal Distance

Y3: Forward Position Orthogonal Distance

DETAILED DESCRIPTION OF THE INVENTION In this detailed description, the subject matter clutch 50 for tractor is explained with references to examples without forming any restrictive effect only in order to make the subject more understandable.

The clutch 50, used for the control of movement transfer from the motor to the transmission, comprises a cover 51 having a body portion in circular form around an axis Y and a pressure plate 52 connected to the cover by using an adjustable lever 10. The axis Y corresponds also to axis of rotation of the clutch. The cover 51 comprises a friction surface. A conventional clutch disc is interposed between the pressure plate 52 and the friction surface of the cover 51 .

In Figure 1 , the general view of the clutch system 50 where the subject matter adjustable lever 10 is provided is given. The adjustable lever 10 is provided between the cover 51 and the plate 52 provided in the clutch 50 and it is connected by means of a helical spring 53. With reference to Figure 2, the adjustable lever 10 essentially comprises a fixed arm 40 positioned between said spring 53 and said plate 52, an elbow arm 20 connected to the cover 51 through a region thereof, and a movable arm 30 provided between said elbow arm 20 and said fixed arm 40. The press load, formed by the adjustable lever 10 and the plate 52, and stored in the spring 53 in course condition, are used in forming different adjustable lever proportions for obtaining different pedal load values.

In Figure 3, the elbow arm 20 comprises two carrier sheets 21 positioned mutually, a sheet connection pin 22 connecting said carrier sheets 21 to each other, a contact part 23 positioned on said sheet connection pin 22 and at one end of the carrier sheets 21 , an adjustment screw 25 positioned between the carrier sheets 21 by means of a screw adjustment pin 24, a casing 26 connected to said adjustment screw 25 and a cover connection pin 27 connected to the cover 51 by means of connecting the carrier sheets 21 from another end of the carrier sheets 21. The carrier sheet 21 comprises a sheet connection hole 21 1 where the sheet connection pin 22 placed thereon, a screw connection hole 212 where the screw adjustment pin 24 is placed, an adjustment hole 213 where said movable arm 30 and said casing 26 are connected and a cover connection hole 214 where said cover connection pin 27 is placed. The cover connection hole 214 and the cover connection pin 27 also represent a support point M. The casing 26 comprises a base 261 , flaps 262 extending at the two sides of said base 261 and pin holes 263 embodied at said flaps 262. While the adjustment screw 25 is positioned at the base 261 part of said casing 26, one of the flaps 262 is connected to the movable arm 30 and the other one of the flaps 262 is connected to the adjustment hole 213.

For example, the adjustment hole 213 has an oblong shape.

The casing 26 is attached onto the adjustment screw 25 by using a riveted connection. However, the adjustment screw 25 can rotate relative to the casing due to the presence of an axial clearance between the rivet head and the casing 26. The movable arm 30 comprises a support hole 31 at one end thereof and a lower support hole 32 at a lower end thereof. A support pin 33 is positioned at said support hole 31 and while said support pin 33 connects the casing 26 and the elbow arm 20 to each other, at the same time, it is placed to the adjustment holes 213. A lower support pin 34 is positioned at said lower support hole 32 and the fixed arm 40 and the movable arm 30 are connected through said lower support pin 34. The fixed arm 40 extends inside said spring 53 and there is a pin housing 41 at the end thereof. The lower support pin 34 is placed to said pin housing 41. The movable arm 30 has two freedom degrees. By means of the movement of the movable arm 30, locking of the mechanism can be prevented.

In the direction of the customer requests realized by means of the adjustable lever 10, the pedal load can be determined during production. In this direction, in order to provide obtaining of the desired pedal load, the press load, stored in the fixed arm 40 at a fixed value and provided by the spring 53, is obtained through adjustable lever proportions which are changeable through the movable arm 30 and the elbow arm 20 of the adjustable lever 10. Afterwards, it is transferred to the pedal through the contact part 23. Obtaining different adjustable lever proportions is provided by means of the adjustment screw 25. In this direction, the object is to change the position of the support pin 33, provided at a support point horizontal distance X and a support point orthogonal distance Y with respect to the cover connection pin 27, by means of the movement of the support pin 33 in the adjustment hole 213. In order to realize this change, first of all, the adjustment screw 25 can be rotated by means of access from outside, and depending on this, the support pin 33 can be shifted. In Figure 4, the backward adjustment position A, the middle adjustment position B and the forward adjustment position C, which occur depending on the different positions of the support pin 33, are given as example. For the most forward position of the support pin 33, the position in the adjustment hole 213 is at the backward adjustment position A. This condition provides minimization of the backward position horizontal distance X1 and the maximization of the backward position orthogonal distance Y1 by means of moving of the movable arm 30 and the elbow arm 20. The backward adjustment position A is the most backward position of the support point M and it is the position where the adjustable lever proportion is maximized, and in related to this, the pedal load is minimized.

The backward adjustment position A of the support point is obtained by screwing the adjustment screw in a manner to move radially the adjustment screw in the opposite direction of the axis Y.

For the middle position of the support pin 33, the position in the adjustment hole 213 is in the middle adjustment position B. This condition provides the middle position horizontal distance X2 and the middle position orthogonal distance Y2 to obtain an average value by means of movement of the movable arm 30 and the elbow arm 20. For the most backward position of the support pin 33, the position in the adjustment hole 213 is in its most forward adjustment position C. This condition provides maximization of the forward position horizontal distance X3 and minimization of the forward position orthogonal distance Y3 by means of movement of the movable arm 30 and the elbow arm 20.

The forward adjustment position C is the position where the support point M is most forward and where the adjustable lever proportion is minimized, and in relation to this, the pedal load is maximized.

The forward adjustment position C of the support point is obtained by screwing the adjustment screw in a manner to move radially the adjustment screw in the direction of the axis Y. By means of the subject matter adjustable lever 10, the minimum and maximum values of the pedal load is obtained in the most forward and most backward positions of the support point M, and the pedal loads, which correspond to the values between the forward position and backward position, are changing. Thus, the position of the support point M is changed for obtaining the desired pedal load and the adjustable lever proportion is determined. These processes are realized such that the adjustable lever height is fixed. Thus, there remains no need to change the press plate and the adjustable lever components for the changes in the pedal load. In such an embodiment, the adjustment of the lifting and bearing load is facilitated and moreover, the production tolerances can be eliminated. 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.