Torque limiter

Abstract

The invention relates to a torque limiter (A) connected to the motor / gearbox / reducer (power unit), etc. side of the driveshaft, which prevents damage to other drivetrain units by sudden peak torque from the power unit (electric motor, internal combustion engine or hybrid engine) or to the power unit or driveshaft by reaction torque.

Description

[0001] Torque Limiter

[0002] Technical Field

[0003] The invention relates to a torque limiter that can be integrated into the driveshaft and is activated according to the target torque value in order to prevent damage caused by sudden peak torque in the driveshafts or drivetrain.

[0004] State of the Art

[0005] Nowadays, there is a need for systems that will prevent driveshaft failures that occur with sudden torque increase (peak torque). In particular, there is a need for a torque limiter positioned at the driveshaft motor / reducer / transmission output to prevent malfunctions caused by sudden peak torque in electrically driven systems.

[0006] Torque limiters in current applications protect against damage caused by shock loads in the driveshafts of agricultural vehicles. Generally, friction disc, shear bolt, radial pin and cam clutch types are used in these vehicles. In shear bolt torque limiters, torque transmission is prevented by cutting the bolt, but the system cannot be put into operation in a short time without replacing the shear bolt without human intervention. Having more than one pad in a torque limiter with brake pads makes the maintenance of the torque limiter difficult and also increases its costs. However, said torque limiter systems include products developed specifically for the driveshafts of agricultural vehicles. In the industrial market, there is a need for a torque limiter that will protect against sudden load changes, for example, sudden peak torque occurrences due to operation in rolling mills, sudden shock damage to the system caused by electrical voltage fluctuations or interruptions. In addition, in the literature research, it is determined that the torque limiter in the industrial market and agricultural vehicles is limited and protected by patents. As a matter of fact, it has been observed that companies that make torque limiter applications have developed them specifically for industrial applications and agricultural vehicles.

[0007] In the patent research of the state of the art, US10436261 has been found regarding the subject. Said document is about the roller type torque limiter. The roller type torque limiter moves axially moving balls between the peripheral teeth and the inner surface of the connection flange. During overload, the bails change place in the housing and prevent the rotation movement from being transmitted instantly until normal load occurs. However, the spherical bearing roller slots lined up on the pressure flange surface and the internal form of the bearing cover in contact with the rollers apply perpendicular force to the rollers. Additionally, in mentioned document the torque limiter is used only in industrial applications.

[0008] In the document numbered CN108869572A, which is in the state of the art, the protective mechanical system approach that prevents excessive torque is explained. In said document, it is mentioned that the ball slots in the pressure flange have a spherical bearing structure, and the hub shaft, which applies radial force to the balls in the pressure flange, can carry a single row of balls and has a spherical bearing as in the pressure flange. However, this does not include ball slots arranged radially on the pressure flange surface at an angle of 15° (deg ree) between them, a radially tapered geometry on the pressure flange surface with a conical shape at an angle ©f between 50° 80°(degree), and a hub shaft capable of carrying a double row of balls.

[0009] In the document numbered WO201811 1957, which is in the state of the art, different combinations of an electro-mechanical system that absorbs the excessive torque in the sudden torque output of a gearbox containing an electronic control unit (ECU) and does not transfer it to the driveshaft are mentioned. However, there is no mechanical system integrated in the driveshaft to limit excessive torque in the event of a sudden increase in torque.

[0010] As a result of the aforementioned issues and the limited supply of available solutions, it became necessary to carry out an improvement in the relevant technical field.

[0011] Object of the Invention

[0012] The present invention relates to a torque limiter which eliminates the abovementioned disadvantages and brings new advantages to the relevant technical field.

[0013] The main object of the present invention is to provide a torque limiter that can be integrated into the driveshaft and is activated according to the target torque value in order to prevent damage caused by sudden peak torque in the driveshafts or drivetrain.

[0014] The object of the present invention is to provide a torque limiter which is connected by the power unit (motor / gearbox / reducer etc.) of the driveshaft and which prevents damage to the power unit caused by the sudden peak torque from the motor (electric motor, internal combustion engine or hybrid motor) to other drivetrain units or the reaction torque from the wheel / motion transmitting element.

[0015] Another object of the present invention is to provide a torque limiter which automatically activates after the sudden peak torque disappears or decreases and continues to transfer the rotational force received from the power unit to the driveshaft, thus preventing malfunctions and damages to the drivetrain (in the whole system), especially the driveshaft.

[0016] In order to fulfil all of the aforementioned objects and those which may arise from the detailed description, the invention is a torque limiter connected to driveshaft to prevent damage to the driveshafts or drivetrain units due to sudden peak torque, comprising:

[0017] - pressure flange having ball slots on at least one surface and which allows balls in the ball slots to be radially displaced out of the ball slots in the event of a sudden peak torque and at the same time transfers the torque transmitted by the balls, hub shaft, which is connected to the pressure flange and has a groove structure that can be loaded with at least two rows of balls on the same axis and transfers the torque received from the power unit to the driveshaft by carrying it to the pressure flange via the balls,

[0018] - bearing cover on the hub shaft which encloses the balls coaxially by means of ball bearings and prevents the balls from leaving the pressure flange,

[0019] - at least one belleville located in the bearing cover on the hub shaft and pressing the bearing cover in the X-axis direction.

[0020] The structural and characteristic features of the present invention will be understood clearly by the following figures and the detailed description made with reference to these drawings. Therefore, the evaluation shall be made by taking these figures and the detailed description into consideration. Figures Clarifying the Invention

[0021] Figure 1 : Cross-sectional view of the torque limiter that is the subject of the invention. Figure 2: Cross-sectional view of the torque limiter that is the subject of the invention when it is in the engaged.

[0022] Figure 3: Cross-sectional view of the torque limiter that is the subject of the invention when it is in the disengaged.

[0023] Figure 4: Front view of the pressure flange of the torque limiter that is the subject of the invention.

[0024] Figure 5: Sectional view of the pressure flange of the torque limiter that is the subject of the invention.

[0025] Figure 6: Detail view of the pressure flange of the torque limiter that is the subject of the invention.

[0026] Figure 7: View of the hub shaft of the torque limiter that is the subject of the invention. Figure 8: Sectional view of the hub shaft of the torque limiter that is the subject of the invention.

[0027] Figure 9: Front view of the bearing cover of the torque limiter that is the subject of the invention.

[0028] Figure 10: Sectional view of the bearing cover of the torque limiter that is the subject of the invention.

[0029] Description of the Part References

[0030] A. Torque limiter

[0031] 10. Pressure flange

[0032] 11. Ball slot

[0033] 20. Ball

[0034] 30. Gasket

[0035] 40. Bearing cover

[0036] 41. Ball bearing

[0037] 50. Belleville

[0038] 60. Locking washer

[0039] 70. Hub shaft

[0040] 71. Groove

[0041] X. X axis p. p angle a. a angle

[0042] Detailed Description of the Invention

[0043] In this detailed description, the preferred embodiments of the torque limiter (A) are described only for clarifying the subject matter in a manner such that no limiting effect is created.

[0044] The invention relates to a torque limiter (A) connected to the motor / gearbox / reducer (power unit), etc. side of the driveshaft, which prevents damage to other drivetrain components by sudden peak torque from the power unit (electric motor, internal combustion engine or hybrid engine) or to the power unit or driveshaft by reaction torque.

[0045] The torque limiter (A) subject to the invention is positioned at the motor / gearbox / reducer (power unit) connection end of the driveshaft. The torque limiter (A) limits the sudden peak torque that produced by the power unit (initial startup or sudden shock from various causes) and prevents malfunctions and damage to the cardan shaft or other driveline components. In addition, it also prevents damage that may occur in the power unit due to reaction torques reaching the power unit from the powertrain.

[0046] The torque limiter (A) shown in Figure 1 basically comprises a pressure flange (10) with conically shaped ball slots (1 1 ) to accommodate the balls (20), a hub shaft (70) having a groove (71 ) structure which is connected to the pressure flange (10) and which can be loaded with at least two rows of balls (20) coaxially, and a bearing cover (40) connected to the hub shaft (70) and coaxially surrounding the balls (20) and pressed by bellevilles (50) in the direction of the X axis (X). The locking washer (60), which surrounds the hub shaft (70) on its axis, is the element that prevents and fixes the bellevilles (50) from moving back and forth axially in the X axis (X) by applying pressure on the bearing cover (40).

[0047] The pressure flange (10) is the component having the ball slots (11 ) which to provide bearing the balls (20) and thus position the balls (20), so that the balls (20) are radially displaced out of the ball slots (11 ) in the event of a sudden peak torque. At the same time, the pressure flange (10) serves to transmit the torque transferred by the balls (20) or to prevent over torque from being transmitted. The balls (20) move in the grooves (71 ) on the hub shaft (70) in case of over torque, and they come out of the ball slots (11 ) on the pressure flange (10) and interrupt the torque transmission.

[0048] The bellevilles (50) are positioned coaxially to the bearing cover (40) and transfer their force to the balls (20) through the bearing cover (40) by determining their number, dimensions and arrangement (series, parallel or series+parallel) according to the coupling torque. The targeted torque value depends on the belleville (50), and the dimensions and number of the belleville (50) are determined according to the target torque. Bellevilles (50) are mounted in the bearing cover (40) on the hub shaft (70), and by providing pre-load according to the engagement torque to keep the bearing cover (40) under pressure. The system remains engaged thanks to the bearing cover (40) and the balls (20) under pressure.

[0049] The gasket (30) positioned externally between the pressure flange (10) and the bearing cover (40) prevents external contaminants such as dust, mud, and water from entering the torque limiter (A) via the hub shaft (70).

[0050] Figure 1 and Figure 2 show the torque limiter (A) is in the engaged position. Figure 2 shows that the ball (20) sits in the ball slot (11 ) on the pressure flange while the torque limiter (A) is in the engaged position. During engagement, the torque from the power unit is transmitted from the torque limiter (A) to the hub shaft (70) via the torque transmission pressure flange (10) and the ball (20) which fits into the ball slot (1 1 ). Torque is transferred to the driveshaft or other transmission units via the hub shaft (70). As long as the axial reaction force created by the radial force caused by the torque applied through the balls (20) in the ball slot (1 1 ) and the axial force applied to the balls (20) on the bearing cover (40) by the belleville (50) are in balance, the torque limiter (A) remains in the engaged and continues to transmit torque.

[0051] If the torque limiter (A) is deactivated under normal operating conditions with no sudden peak torque, the balls (20) on the pressure flange (10) side automatically reinsert into their ball slots (11 ) and torque transmission continues.

[0052] Figure 3 shows the situation where the torque is not transmitted, the clutch (torque limiter) is disabled, and the torque limiter (A) is in the disengaged. Thus, in Figure 3, it can be seen that the ball (20) comes out of the slot (1 1 ) on the pressure flange (10). If the axial force generated by the torque passing through the balls (20) in the ball slot (11 ) is greater than the axial force exerted by the belleville (50) on the balls (20) on the bearing cover (40), the torque limiter (A) disengages from the engaged position and does not transmit torque. That is, Figure 3 shows the condition where sudden peak torques occur and the torque limiter (A) is in the disengaged.

[0053] Figure 4 shows the view of the pressure flange (10). The pressure flange (10) contains ball slots (11 ) on one surface. For the torque limiter (A) to function properly, the ball slots (1 1 ) are arranged radially on the surface of the pressure flange (10) with an angle P (P) of 15° (degree) between them. The flat surfaces b etween the slots (1 1 ) are the surfaces on which the balls (20) roll when the torque limiter (A) is in the disengaged.

[0054] The condition in which the torque limiter (A) functions is when the sudden peak torque is not transmitted, i.e. the torque limiter is disengaged, and the torque is not transmitted when the balls (20) come out of their slots (1 1 ) and the pressure flange (10) and the hub shaft (70) rotate on the balls (20).

[0055] Figure 5 shows the cross-section of the pressure flange (10), and Figure 6 shows the detail view of the ball slot (1 1 ) located in the pressure flange (10). The ball slots (11 ) arranged radially on the surface of the pressure flange (10) have a conical shaped geometry with an angle of a (a) between 50° and 80°(degree). In the case where t he driveshafts rotate at high speeds (average 2000 rpm and above) and the torque limiter is disengaged, the effect of the impacts that the balls (20) will cause on the slots (11 ) when the balls (20) come out of the slots (1 1 ) and move on the pressure flange (10) and hit the slots (1 1 ) when re-engaged is reduced by the ball slots (11 ) with a conical shaped structure, thus increasing the torque stability of the torque limiter (A) at high speed.

[0056] Figure 7 and Figure 8 show the cross-sectional view of the hub shaft (70). The hub shaft (70) transfers the torque it receives from the power unit to the driveshaft by carrying it to the pressure flange (10) via the balls (20). Accordingly, there are preferably twenty-four grooves (71 ) on the surface of the hub shaft (70), arranged radially at an equal angle with p angle (P) of 15° (degree) and opened to be equal to the diameter of the ball (20). Each of the grooves (71 ) is arranged in a way that can position two balls (20) in mutual contact in the X axis (X) direction (axial direction). Figures 9 and 10 show the front and cross-sectional views of the bearing cover (40). The pressure force of the belleville (50) is transmitted through the point contact of the balls (20) sitting in the ball bearings (41 ) on the bearing cover (40) with the other balls (20) in the axial direction in the groove (71 ), and the system remains in the engaged.

[0057] In the torque limiter (A), torque transmission is transferred to the hub shaft (70) via the pressure flange (10) and the ball (20) sitting on the ball slot (1 1 ). With the point contact of two axially opposed balls (20) located in the groove (71 ), the friction surface between the balls (20) during torque transfer is reduced, wear is reduced, and the life and efficiency of the torque limiter increases.

Claims

CLAIMS1. A torque limiter (A) connected to driveshaft to prevent damage to the driveshafts or drivetrain units due to sudden peak torque, characterized by comprising:- pressure flange (10) having ball slots (1 1 ) on at least one surface and which allows balls (20) in the ball slots (11 ) to be radially displaced out of the ball slots (11 ) in the event of a sudden peak torque and at the same time transfers the torque transmitted by the balls (20), hub shaft (70), which is connected to the pressure flange (10) and has a groove (71 ) structure that can be loaded with at least two rows of balls (20) on the same axis and transfers the torque received from the power unit to the driveshaft by carrying it to the pressure flange (10) via the balls (20),- bearing cover (40) on the hub shaft (70) which encloses the balls (20) coaxially by means of ball bearings (41 ) and prevents the balls (20) from leaving the pressure flange (10),- at least one belleville (50) located in the bearing cover (40) on the hub shaft (70) and pressing the bearing cover (40) in the X-axis direction.

2. The torque limiter (A) according to claim 1 , characterized by comprising a locking washer (60) on said hub shaft (70) which prevents the bellevilles (50) from reciprocating axial movement in the X axis (X) by applying pressure on the bearing cover (40).

3. The torque limiter (A) according to claim 1 , characterized by comprising a gasket (30) positioned externally between said pressure flange (10) and said bearing cover (40), which prevents external materials from entering the torque limiter (A) from outside the hub shaft (70).

4. The torque limiter (A) according to claim 1 , characterized in that; said ball slot (11 ) is arranged radially on the surface of the pressure flange (10) at an angle P (P) of 15° (degree) between them.

5. The torque limiter (A) according to claim 1 , characterized in that; said ball slot (11 ) is radially tapered on the surface of the pressure flange (10) in a tapered geometry with an angle a (a) between 50° 80° (degree).

6. The torque limiter (A) according to claim 1 , characterized in that; said groove(71 ) is arranged radially at an equal angle p (P) 15° (degree) on the surface of the hub shaft (70).

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