Staggered groove type friction coupling

Abstract

A stepped hole in the lower side of a driving shaft sleeve is sleeved with the upper end of an upper friction plate, and the lower side of the upper friction plate is attached to the upper side of the large end of a driven shaft sleeve; the lower side of the large end of the driven shaft sleeve is attached to the upper side of the lower friction plate, and the small end of the driven shaft sleeve is sleeved with an inner hole of the lower friction plate. The six connecting bolts are positioned on the outer sides of the driving shaft sleeve and the connecting plate and are annularly and uniformly distributed; the blades are located between the driving shaft sleeve and the connecting plate, and the inner sides of the blades are connected with the supporting ring. The contact face is in staggered groove contact, staggered groove ventilation is achieved, heat dissipation is more uniform, the annular blow-by grooves divide the contact face into the inner ring and the outer ring, the area of the inner ring is larger than that of the outer ring, the speed difference of the inner ring and the outer ring is compensated, friction force of the inner ring and the outer ring is more uniform, and abrasion resistance and thermal deformation resistance are improved. According to the connecting bolt, the spherical washer is pressed into the conical inner chamfer of the orifice of the threaded hole through the locking nut, hole staggering connection can be achieved, and part interchangeability is better.

Description

Technical Field

[0001] This utility model belongs to the field of mechanical transmission, and in particular to a bolt-type friction coupling. Background Technology

[0002] Friction couplings are devices used to connect two shafts (driving shaft and driven shaft) in different mechanisms, enabling them to rotate together to transmit torque. Friction couplings utilize the friction between friction plates to transmit torque. When the transmitted torque exceeds the sliding torque of the coupling, slippage occurs between the driving and driven sides of the coupling, providing overload protection. When the transmitted torque is lower than the sliding torque, there is no relative slippage between the two sides of the coupling, and it automatically returns to normal operation.

[0003] Bolted friction couplings mainly consist of the following parts: friction plates, clamping springs, connecting bolts, and a housing. The friction plates are located between the driving and driven bushings, transmitting torque through friction. They typically use a planar contact. During non-uniform speed transmission, the transmission system experiences fluctuating loads. The coupling effectively prevents damage to the transmission system caused by excessive instantaneous load during non-uniform speed transmission through slippage between the driving and driven sides. If the load fluctuation is small and the friction coupling's starting frequency is low, the impact is minimal. However, if the load fluctuation is large and the friction coupling's starting frequency is high, it will cause wear on the friction plates. During friction, the friction plates expand due to frictional heat. Uneven heat dissipation between the inner and outer edges of the friction plates results in greater thermal expansion on the inner side than on the outer edge, leading to greater wear on the inner side than on the outer edge. This causes concave localized wear on the contact surface, accelerating friction plate failure and reducing the service life of the friction coupling.

[0004] Although some air-cooled friction clutches now incorporate venting grooves for heat dissipation from the friction plate contact surfaces, to prevent the venting groove steps from colliding and causing jamming and damage during rotational friction, venting grooves are typically only located on one side of the contact surface. These independent venting grooves result in poor uniform heat dissipation. The clamping springs, usually cylindrical helical springs or spring washers, provide clamping force to ensure tight contact of the friction plates during normal operation and eliminate gaps. However, both cylindrical helical springs and spring washers provide eccentric preload, which, due to uneven preload, leads to uneven friction. Uniformity can easily lead to localized wear and accelerate failure; the connecting bolts are usually hexagonal head bolts with nuts, and the preload of the compression spring is adjusted by tightening and loosening the bolts. When adjusting this type of structure, a clamping tool is required to hold one end so that the clamping tool can be used to adjust the other end. The transmission system must reserve sufficient space for the clamping tool to operate, which occupies a lot of space; when the driving and driven sides slip, the connecting bolts will also be subjected to shear force caused by friction, resulting in poor load-bearing capacity; the bolt holes for the connecting bolts must be of the same size and aligned with each other, resulting in poor interchangeability of parts. Utility Model Content

[0005] The purpose of this utility model is to overcome the shortcomings of the prior art and provide a slotted friction coupling that can solve local wear, prevent local overheating, and is easy to adjust.

[0006] The present invention provides a grooved friction coupling comprising: blades, a support ring, a drive bushing, connecting bolts, a driven bushing, friction plates, and a connecting plate. The drive bushing is located on the upper side of the coupling, with its lower stepped hole fitted onto the upper end of the upper friction plate for a fixed connection. The lower side of the upper friction plate is attached to the upper side of the large end of the driven bushing. The lower side of the large end of the driven bushing is attached to the upper side of the lower friction plate, and its small end is fitted into the middle hole of the lower friction plate. The lower end of the lower friction plate is fitted into the upper stepped hole of the connecting plate for a fixed connection. The connecting bolts connect the drive bushing and the connecting plate, with six ring-shaped pieces evenly distributed on the outer side of the drive bushing and the connecting plate. The support ring is fitted onto the outer edge of the drive bushing and the connecting plate, and the blades are evenly distributed in rings at the gap between the drive bushing and the connecting plate, with their inner sides fixedly connected to the support ring.

[0007] The drive bushing is a disc-type structure, with a small upper end and a large lower end. The middle hole has a keyway, the lower side has a stepped hole, and the outer side has six bolt holes evenly distributed in an annular shape. The upper hole opening has a conical inner chamfer. The inner side of the large end and the outer side of the small end have annularly distributed air inlets, which are aligned with and connected to the air vents of the friction plate.

[0008] The friction plate has a disc structure, and the position where it fits with the drive bushing and the connecting plate is a smooth surface. The outer contact surface is provided with radially distributed ventilation grooves and annular air leakage grooves. The inner side of each ventilation groove is provided with annularly distributed ventilation holes that are aligned with and connected to the air inlet of the drive bushing.

[0009] The driven bushing has a disc-shaped structure, with a large upper end and a small lower end. The central hole has a keyway, and the upper and lower mating surfaces are provided with arc-shaped venting grooves and annular air leakage grooves.

[0010] The connecting plate is a disc-type structure with a central hole on one side and a stepped hole on the upper side. The inner hole of the central hole is located outside the vent hole of the lower friction plate. There are six bolt holes evenly distributed in a ring on the outer side, and the lower hole opening has a conical inner chamfer.

[0011] The connecting bolt includes: a lock nut, a disc spring, a spherical washer, and a double-ended screw. The lock nut is fitted onto the double-ended screw and located on the inner side of the flat square at both ends of the double-ended screw. The disc spring is fitted onto the double-ended screw and located on the inner side of the lock nut at both ends. The spherical washer is fitted onto the double-ended screw and located on the inner side of the disc spring.

[0012] The double-ended screw has flat squares at both ends.

[0013] The support ring is a ring-shaped steel wire mesh.

[0014] The blade is a corrugated plate.

[0015] This invention, when the drive and driven shafts rotate, drives the blades to rotate, generating centrifugal force and expelling air from the coupling cavity. This causes a pressure drop within the coupling cavity, creating a pressure difference. External gas enters the ventilation slots of the drive shaft sleeve and friction plates through the air inlet and vent holes, achieving air cooling. The blades are corrugated plates, with a corrugated structure forming flow channels to facilitate laminar flow and also acting as reinforcing ribs. The ventilation slots of the friction plates are radial, while the ventilation slots of the driven shaft sleeve are arc-shaped. The grooves on the two mating surfaces are staggered, which allows for ventilation between the grooves and prevents the grooves on the two contact surfaces from colliding with each other during rotation and friction. Because the inner linear velocity of the driven bushing and the friction plate is less than that of the outer linear velocity when they rotate and rub, this invention provides an annular air leakage groove on the contact surface of the driven bushing and the friction plate, dividing the driven bushing and the friction plate into inner and outer rings. The contact area of ​​the inner ring is larger than that of the outer ring, making the friction force and frictional heat of the inner and outer rings more uniform and improving the ventilation effect of the staggered grooves.

[0016] This utility model uses connecting bolts for fastening. By tightening the locking nuts at both ends of the connecting bolts, and pressing the spherical washer into the conical chamfer inside the threaded hole of the drive shaft sleeve and connecting plate, staggered hole connection can be achieved. The stress decomposition effect of the chamfered surface inside the cone can decompose the shear stress during operation. The disc spring can provide a uniform preload around the circumference without off-center load, and can better fit the gap caused by friction plate wear through rebound. By clamping either end of the double-ended screw, the locking nut can be adjusted at either end to adjust the preload.

[0017] Compared with the existing technology, the present invention has the following advantages:

[0018] 1. This utility model has good resistance to thermal deformation. The venting groove of the friction plate is a radial venting groove, and the venting groove of the driven bushing is an arc-shaped venting groove. The venting grooves of the two mating surfaces are in staggered contact, which can realize inter-groove ventilation. The contact surface of the driven bushing and the friction plate is provided with an annular air leakage groove, which further improves the staggered ventilation effect, makes heat dissipation more uniform, and solves the problem of uneven local thermal expansion. The venting groove and the annular air leakage groove divide the mating surface from a whole mating to a partial mating, avoiding overall expansion and contraction. Moreover, the contact area of ​​the inner ring is larger than that of the outer ring, which compensates for the difference in linear velocity between the inner and outer rings, and the frictional heat is more uniform. It effectively reduces thermal expansion deformation and cooling contraction deformation.

[0019] 2. This utility model has strong wear resistance. The contact surface of the driven shaft sleeve and the friction plate is provided with an annular air leakage groove, which divides the driven shaft sleeve and the friction plate into inner and outer rings. The contact area of ​​the inner ring is larger than that of the outer ring, which compensates for the difference in linear velocity between the inner and outer rings. The disc spring can provide a uniform circumferential preload without off-center load. The preload is more uniform and can better fit the gap caused by the wear of the friction plate through rebound. This makes the friction force of the inner and outer rings more uniform and the wear is more uniform. It avoids eccentricity and movement caused by gaps.

[0020] 3. This utility model has stronger load-bearing capacity and higher safety. The venting grooves on the contact surfaces of the friction plate and the driven bushing are staggered, which can prevent the grooves on the two contact surfaces from colliding with each other during mutual rotation and friction, causing jamming and damage. The spherical washer of the connecting bolt decomposes the shear stress during operation through the stress decomposition effect of the chamfered inclined surface inside the bolt hole cone, effectively improving the load-bearing capacity.

[0021] 4. This utility model has a high starting frequency, strong wear resistance, good heat deformation resistance, strong load-bearing capacity, and high safety, which can effectively improve the starting frequency.

[0022] 5. This utility model has strong versatility. The connecting bolts of this utility model can achieve staggered hole connection by locking nuts at both ends and pressing the spherical washer into the conical chamfer of the threaded hole opening of the drive shaft sleeve and the connecting plate. The bolt holes of the connecting bolts do not need to be the same size and can be aligned with each other, and the parts have good interchangeability.

[0023] 6. This utility model is easy to adjust and occupies little space. By clamping either end of the flat square end of the double-ended screw, the locking nut can be adjusted at either end to adjust the preload. There is no need to clamp at both ends. The transmission system only needs to reserve space on one side for the clamping tool to operate.

[0024] 7. This utility model has good ventilation and air permeability. The blades are corrugated plates, and the corrugated structure forms a flow channel, which is conducive to generating laminar flow and acts as a reinforcing rib to improve the structural strength of the blades. It can effectively improve the load-bearing capacity of the blades and increase the exhaust volume. The support ring is a ring-shaped steel wire mesh, which has good connection and support effect, good air permeability, and low wind resistance. Attached Figure Description

[0025] Figure 1 A schematic diagram of the structure of this utility model;

[0026] Figure 2 Top view of this utility model;

[0027] Figure 3 A top view of the driven bushing of this utility model;

[0028] Figure 4 A bottom view of the driven bushing of this utility model;

[0029] Figure 5 A schematic diagram of the friction pad bonding surface of this utility model;

[0030] Figure 6 A side view of the blade of this utility model;

[0031] Figure 7 Schematic diagram of local wear in the grooved friction of this utility model;

[0032] Figure 8 Schematic diagram of the connecting bolt structure of this utility model;

[0033] Figure 9 A schematic diagram of localized wear caused by existing planar friction. Detailed Implementation

[0034] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 As shown, a grooved friction coupling includes: blades 1, support ring 2, driving bushing 3, connecting bolts 4, driven bushing 5, friction plates 6, and connecting plate 7. The driving bushing 3 is located on the upper side of the coupling, and its lower stepped hole is fitted into the upper end of the upper friction plate 6 for fixed connection. The lower side of the upper friction plate 6 is attached to the upper side of the large end of the driven bushing 5. The lower side of the large end of the driven bushing 5 is attached to the upper side of the lower friction plate 6, and its small end is fitted into the middle hole of the lower friction plate 6. The lower end of the lower friction plate 6 is fitted into the stepped hole on the upper side of the connecting plate 7 for fixed connection. The connecting bolts 4 connect the driving bushing 3 and the connecting plate 7, and six rings are evenly distributed on the outer side of the driving bushing 3 and the connecting plate 7. The support ring 2 is fitted into the outer edge of the driving bushing 3 and the connecting plate 7. The blades 1 are evenly distributed in a ring at the gap between the driving bushing 3 and the connecting plate 7, and their inner sides are fixedly connected to the support ring 2.

[0035] The drive bushing 3 is a disc-type structure, with a small upper end and a large lower end. The middle hole has a keyway, the lower side has a stepped hole, and the outer side has six bolt holes evenly distributed in an annular shape. The upper side hole opening has a conical inner chamfer. The inner side of the large end and the outer side of the small end have annularly distributed air inlets P, which are aligned with and connected to the air vents Q of the friction plate 6.

[0036] The friction plate 6 is a disc structure. The position where it fits with the drive bushing 3 and the connecting plate 7 is a smooth surface. The outer contact surface is provided with radially distributed ventilation grooves and annular air leakage grooves. The inner side of each ventilation groove is provided with annularly distributed ventilation holes Q that are aligned with and connected to the air inlet holes P of the drive bushing 3.

[0037] The driven bushing 5 is a disc-type structure, with a large upper end and a small lower end. The central hole is provided with a keyway, and the upper and lower mating surfaces are provided with arc-shaped venting grooves and annular air leakage grooves.

[0038] The connecting plate 7 has a single-sided central hole and a disc-like structure. It has a stepped hole on the upper side, and the inner hole of the central hole is located outside the vent Q of the lower friction plate 6. There are six bolt holes evenly distributed in an annular shape on the outer side, and the lower hole opening has a conical inner chamfer.

[0039] The connecting bolt 4 includes: a locking nut 4-1, a disc spring 4-2, a spherical washer 4-3, and a double-ended screw 4-4. The locking nut 4-1 is sleeved on the double-ended screw 4-4 and located inside the flat sides at both ends of the double-ended screw 4-4; the disc spring 4-2 is sleeved on the double-ended screw 4-4 and located inside the locking nuts 4-1 at both ends; and the spherical washer 4-3 is sleeved on the double-ended screw 4-4 and located inside the disc spring 4-2.

[0040] The double-ended screw 4-4 has flat squares at both ends.

[0041] The support ring 2 is a ring-shaped steel wire mesh.

[0042] The blade 1 is a corrugated plate.

[0043] like Figure 9 As shown, the friction plate 8 without ventilation grooves has a disc structure. Before wear, the right side is a smooth surface, and after wear, it becomes a concave surface.

Claims

1. A misaligned groove friction coupling comprising: The blade, the support ring, the driving shaft sleeve, the connecting bolt, the driven shaft sleeve, the friction plate and the connecting plate are arranged in sequence, the driving shaft sleeve is located on the upper side of the coupling, the lower side stepped hole of the driving shaft sleeve is sleeved with the upper end of the upper friction plate, the upper friction plate is fixedly connected with the upper side stepped hole of the connecting plate, the lower side of the upper friction plate is attached to the upper side of the driven shaft sleeve, the lower side of the driven shaft sleeve is attached to the upper side of the lower friction plate, the small end of the driven shaft sleeve is sleeved with the middle hole of the lower friction plate, the lower end of the lower friction plate is sleeved with the upper side stepped hole of the connecting plate, the connecting bolt is connected with the driving shaft sleeve and the connecting plate, and the six annulars are uniformly distributed on the outer side of the driving shaft sleeve and the connecting plate.

2. A misaligned groove type friction coupling according to claim 1, wherein: The support ring is sleeved with the outer edge of the driving shaft sleeve and the connecting plate, the blade is annularly and uniformly distributed in the gap position between the driving shaft sleeve and the connecting plate, the inner side of the blade is fixedly connected with the support ring, the inner side of the large end of the driving shaft sleeve and the outer side of the small end of the driving shaft sleeve are provided with annularly and uniformly distributed air inlet holes which are opposite to the air holes of the friction plate, the outer side of the friction plate is provided with radially and uniformly distributed air grooves and annular air bypass grooves, the inner side of the air grooves is provided with annularly and uniformly distributed air holes which are opposite to the air inlet holes of the driving shaft sleeve, and the upper and lower sides of the driven shaft sleeve are provided with arc air grooves and annular air bypass grooves.

3. A misaligned slotted friction coupling according to claim 1, wherein: The outer side of the driving shaft sleeve is provided with six annularly and uniformly distributed bolt holes, and the upper side hole is conical and internally chamfered.

4. A misaligned slotted friction coupling according to claim 3, wherein: The connecting bolt comprises a locking nut, a disc spring, a spherical gasket and a double-headed screw rod, the locking nut is located on the inner side of the flat square at both ends of the double-headed screw rod, the disc spring is located on the inner side of the locking nut at both ends, and the spherical gasket is located on the inner side of the disc spring.

5. A misaligned slotted friction coupling according to claim 1, wherein: The double-headed screw rod is provided with a flat square at both ends.

6. A misaligned slotted friction coupling according to claim 1, wherein: The support ring is a ring-shaped steel wire mesh. The blade is a wave-shaped plate.

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