An automatic tensioner with out-of-plane frictional double damping

Abstract

The application discloses a kind of automatic tensioner of double-damping of out-of-plane friction, including base, main shaft, tensioning arm, helical spring and damping piece, one end of base is opened, first half cup structure is equipped on base, main shaft is coaxially installed in base, the lower end of main shaft is interference fit with the bottom of base, axial through-hole is equipped on main shaft, second half cup structure and belt pulley connecting structure are equipped on tensioning arm, tensioning arm rotates at the opening of base, helical spring is helical torsion spring, coaxially is set on main shaft, damping piece includes the upper damping piece and lower damping piece of center symmetry arrangement.The application provides a kind of automatic tensioner of double-damping of out-of-plane friction, upper damping piece is equipped between tensioning arm and helical spring, lower damping piece is equipped between base and helical spring, by out-of-plane friction, stable, higher, evenly distributed and asymmetric damping is generated, to attenuate the vibration of tensioner, increase the life of tensioner.

Description

TECHNICAL FIELD

[0001] The present application relates to the tensioner of the automobile belt drive system, and particularly to an automatic tensioner with double damping of different planes and friction. BACKGROUND

[0002] The tensioner is widely used in the belt drive system, in order to effectively reduce the vibration of the tensioner in the work, and reduce the vibration amplitude of the tensioner, improve the comfort, generally use damping device in the tensioner, and the existing damping device cannot provide a larger damping force in a wide range of working conditions, so that a larger vibration and abnormal sound are generated in some specific belt drive systems, which greatly affects the driving experience; and some tensioners that can provide a larger damping force use single damping member or symmetrically arranged double damping members as damping devices, which have poor friction effect, uneven wear of damping members during work, low precision, and cannot meet the working requirements of the tensioner of the automobile belt drive system.

[0003] For example, a "damping enhanced automatic belt tensioner" disclosed in Chinese patent document, with publication number CN211009770U, includes a base, a main shaft, a rotating tensioning arm, a spiral spring, a supporting ring and a friction ring. The spiral spring is a spiral torsion spring without bent legs at both ends, which is sleeved on the main shaft. The supporting ring is coaxially sleeved outside the spiral spring. The friction ring is a circular ring member with an opening. The friction ring is positioned and attached to the outer circumferential surface of the supporting ring. Two wedge-shaped blocks are arranged at the opening of the friction ring. The upper block on the rotating tensioning arm is clamped in the opening of the friction ring. The upper end of the spiral spring abuts against one wedge-shaped block of the friction ring and makes the wedge-shaped block abut against the upper block. The spiral spring drives the rotating tensioning arm to rotate around the main shaft, so that the pulley on the rotating tensioning arm is attached to the engine belt. The disadvantage is that the single damping member is used as the damping device, the friction effect is poor, the damping member is unevenly worn during work, the precision is low, and the working requirements of the tensioner of the automobile belt drive system cannot be well met. SUMMARY

[0004] The purpose of the present application is to overcome the problems in the prior art that the single damping member or the symmetrically arranged double damping members are used as the damping device, the friction effect is poor, the precision is low, and the working requirements of the tensioner of the automobile belt drive system cannot be well met. An automatic tensioner with double damping of different planes and friction is provided. An upper damping member is arranged between the tensioning arm and the spiral spring, and a lower damping member is arranged between the base and the spiral spring. Through the friction of different planes, stable, high, uniformly distributed and asymmetric damping is generated to attenuate the vibration of the tensioner and increase the service life of the tensioner.

[0005] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0006] An automatic tensioner with double damping of different planes and friction comprises:

[0007] A base, one end of the base is open, and the base is provided with a first half-cup structure;

[0008] A main shaft is coaxially installed in the base, and the lower end of the main shaft is in interference fit with the bottom of the base, and the main shaft is provided with an axial through hole;

[0009] A tensioning arm is provided with a second half-cup structure and a belt pulley connecting structure, and the tensioning arm rotates at the opening of the base;

[0010] A helical spring is a helical torsion spring, which is coaxially sleeved on the main shaft;

[0011] A damping member, the damping member includes an upper damping member and a lower damping member arranged centrally symmetrically, the upper damping member is arranged between the mounting inner surface of the tensioning arm and the helical spring, and the lower damping member is arranged between the mounting inner surface of the base and the helical spring.

[0012] By implementing the above technical scheme, the first cup-shaped structure and the second cup-shaped structure form a cup-shaped structure with a certain gap, the gap is the position of the warning angle, which is convenient for process assembly, and the spring warning angle is left, which is convenient for controlling the working angle of the tensioner. The lower end of the main shaft is in interference fit with the bottom of the base to form a receiving space in the base. The base is fixed and installed on the cover of the engine through the axial hole by bolts. The present application can provide larger and stable damping, so that the drive system will not fail due to damping attenuation. Two damping members are placed centrally symmetrically in the tensioner, thereby providing larger damping together. In the running process of the tensioner, the outer walls of the lower damping member and the upper damping member respectively fit the half-cup structure inner walls of the tensioning arm and the base, and the upper damping member and the lower damping member are centrally symmetrically arranged one above the other, and generate stable, high, uniform and asymmetric damping through the friction of different surfaces, so as to attenuate the vibration of the tensioner and increase the service life of the tensioner.

[0013] As preferred, the bottom of the base is provided with a first positioning block for matching the end face of the lower damping member and a first spring stopper for preventing the spring from tilting, and the outer wall of the lower damping member is attached to the inner wall of the tensioning arm when the tensioner is in operation. The first positioning block is attached to the end face of the lower damping member, so that the first positioning block is connected to the lower damping member head to tail, and the force can be transmitted between the first positioning block and the lower damping member. The first spring stopper is located in the opposite face of the lower damping member at 180°, and presses against the lower end of the spring to prevent the spring from tilting. The outer wall of the lower damping member is attached to the inner wall of the second half cup-shaped structure of the tensioning arm, and the lower damping member is subjected to the lateral extrusion force of the spring under the action of the spring torsion force, so that the outer wall of the lower damping member is attached to the inner wall of the tensioning arm for friction, thereby generating damping. The second half cup-shaped structure of the tensioning arm needs to be machined to reduce the surface roughness, so that the first outer wall of the lower damping member is more stable when it is in contact with the second half cup-shaped structure for friction, thereby increasing the service life of the lower damping member.

[0014] As preferred, the base is further provided with a warning angle limiting groove, and the second half cup-shaped structure has a lower end face formed by a side protrusion, and the warning angle limiting groove is assembled and limited with the lower end face. In the pre-installed state, the lower end face of the tensioning arm is placed on the upper end face of the base, and after rotating a certain warning angle, the tensioning arm is pressed down, so that the lower end face enters the warning angle limiting groove, thereby controlling the stroke and angle of the tensioner in operation.

[0015] As preferred, the tensioning arm is provided with a rotating through hole in the middle, which can be rotated and connected to the upper end of the main shaft. A bushing is arranged between the main shaft and the rotating through hole of the tensioning arm. The bushing is a cylindrical ring member with a wear-resistant coating on the inner side. The inner hole of the bushing is in clearance fit with the main shaft, and the rotating through hole of the tensioning arm is in interference fit with the bushing.

[0016] As preferred, the bottom of the base is provided with a first positioning block for matching the end face of the lower damping member and a first spring stopper for preventing the spring from tilting, and the outer wall of the lower damping member is attached to the inner wall of the tensioning arm when the tensioner is in operation. The first positioning block is attached to the end face of the lower damping member, so that the first positioning block is connected to the lower damping member head to tail, and the force can be transmitted between the first positioning block and the lower damping member. The first spring stopper is located in the opposite face of the lower damping member at 180°, and presses against the lower end of the spring to prevent the spring from tilting. The outer wall of the lower damping member is attached to the inner wall of the second half cup-shaped structure of the tensioning arm, and the lower damping member is subjected to the lateral extrusion force of the spring under the action of the spring torsion force, so that the outer wall of the lower damping member is attached to the inner wall of the tensioning arm for friction, thereby generating damping. The second half cup-shaped structure of the tensioning arm needs to be machined to reduce the surface roughness, so that the first outer wall of the lower damping member is more stable when it is in contact with the second half cup-shaped structure for friction, thereby increasing the service life of the lower damping member.

[0017] As preferred, the two ends of the spiral spring are provided with straight edges, including a lower end straight edge and an upper end straight edge.

[0018] As preferred, a first spring hanging straight slot is arranged in the middle of the lower damping member, the lower damping member is placed on the base, the first spring hanging straight slot faces upward, and the lower end straight edge is sleeved into the first spring hanging straight slot on the lower damping member.

[0019] As preferred, a second spring hanging straight slot is arranged in the middle of the upper damping member, the upper damping member is placed on the base, the second spring hanging straight slot faces downward, and the upper end straight edge is sleeved into the second spring hanging straight slot.

[0020] As preferred, the pulley connecting structure is connected with the pulley, the pulley is installed on the tensioning arm through a bearing, a dust cover and a bolt, and the pulley connecting structure is provided with a rotatable pulley which is attached to the engine belt.

[0021] The present application has the following beneficial effects: (1) the upper damping member is arranged between the tensioning arm and the spiral spring, the lower damping member is arranged between the base and the spiral spring, stable, high, uniformly distributed and asymmetric damping is generated through the friction of different surfaces, so as to attenuate the vibration of the tensioner and increase the service life of the tensioner; (2) a large and stable damping can be provided, so that the driving system will not fail due to damping attenuation, two damping members are placed in the tensioner in a one-up and one-down central symmetry, so as to jointly provide a large damping; (3) in the preloaded state, the lower end surface of the tensioning arm is placed on the upper end surface of the base, the tensioning arm is pressed downward after rotating a certain warning angle, so that the lower end surface enters the warning angle limiting groove, thereby controlling the stroke and angle of the tensioner during operation. BRIEF DESCRIPTION OF DRAWINGS

[0022] The present application will be further described below in combination with the drawings and examples.

[0023] Figure 1 is an explosion view of the present application;

[0024] Figure 2 is an isometric view of the present application;

[0025] Figure 3 is a structural schematic view of the base in the present application;

[0026] Figure 4 is a structural schematic view of the tensioning arm in the present application;

[0027] Figure 5 is a structural schematic view of the spiral spring in the present application;

[0028] Figure 6 is a structural schematic view of the lower damping member in the present application;

[0029] Figure 7is the structural schematic view of the upper damping member in the application;

[0030] Figure 8 is the schematic view of the upper damping member generating damping force in the application;

[0031] Figure 9 is the schematic view of the lower damping member generating damping force in the application.

[0032] In the figure: base 1, first positioning clamping block 101, first spring clamping block 102, first half cup structure 103, early warning angle limiting groove 104, lower damping member 2, first spring hanging mouth straight groove 201, first end surface 202, first outer wall 203, helical spring 3, lower end straight edge 301, upper end straight edge 302, tensioning arm 4, rotary through hole 401, second half cup structure 402, second positioning clamping block 403, second spring clamping block 404, lower end surface 405, bushing 5, main shaft 6, axial hole 601, upper damping member 7, second spring hanging mouth straight groove 701, second end surface 702, second outer wall 703, belt pulley 8, bearing 9, dust cover 10, bolt 11. DETAILED DESCRIPTION Specific embodiment one:

[0034] As Figure 1 Or Figure 2 Or Figure 3 Or Figure 4As shown, a kind of out-of-plane friction double-damping automatic tensioner, including base 1, lower damping member 2, coil spring 3, tensioning arm 4, bushing 5, main shaft 6, upper damping member 7, pulley 8, bearing 9, dust cover 10 and bolt 11;Base 1 one end opening, base 1 is equipped with first half cup structure 103, main shaft 6 is coaxially installed in base 1, the lower end of main shaft 6 is in interference fit with the bottom of base 1, main shaft 6 is equipped with axial through hole 601, tensioning arm 4 is equipped with second half cup structure 402 and pulley connecting structure, tensioning arm 4 rotates at the opening of base 1, coil spring 3 is spiral torsion spring, coaxially sleeved on main shaft 6, damping member includes upper damping member 7 and lower damping member 2 arranged symmetrically, upper damping member 7 is arranged between the installation inner surface of tensioning arm 4 and coil spring 3, lower damping member 2 is arranged between the installation inner surface of base 1 and coil spring 3.The bottom of base 1 is equipped with first positioning block 101 for matching the end face of lower damping member 2 and first spring stopper 102 for preventing coil spring 3 from tilting, the outer wall of lower damping member 2 is attached to the inner wall of tensioning arm 4 when tensioner operates.Base 1 is also equipped with early warning angle limiting groove 104, second half cup structure 402 one side protrusion forms lower end surface 405, early warning angle limiting groove 104 is assembled with lower end surface 405 limit.Tensioning arm 4 is equipped with rotary through hole 401 in the middle, which can rotate and connect to the upper end of main shaft 6, bushing 5 is arranged between main shaft 6 and rotary through hole 401 of tensioning arm 4, bushing 5 is cylindrical ring member, with wear-resistant coating on the inside, the inner hole of bushing 5 is in clearance fit with main shaft 6, the rotary through hole 401 of tensioning arm 4 is in interference fit with bushing 5.The bottom of tensioning arm 4 is equipped with second positioning block 403 for matching the end face of upper damping member 7 and second spring stopper 404 for preventing coil spring 3 from tilting, the outer wall of upper damping member 7 is attached to the inner wall of base 1 when tensioner operates.Pulley connecting structure is connected with pulley 8, pulley 8 is installed on tensioning arm 4 through bearing 9, dust cover 10 and bolt 11.

[0035] The first cup-shaped structure 103 and the second cup-shaped structure 402 form a cup-shaped structure with a gap, the gap is the position of the early warning angle limiting groove 104, which is convenient for process assembly, and the spring early warning angle is left, which is convenient for controlling the working angle of the tensioner. The lower end of the main shaft 6 is in interference fit with the bottom of the base 1 to form a receiving space in the base 1. The base 1 is fixed and installed on the cover of the engine through the axial hole 601 by means of bolts. The present application can provide larger and stable damping, so that the driving system will not fail due to damping attenuation. Two damping members are placed in the tensioner in a top and bottom center symmetry, thereby providing larger damping together. In the running process of the tensioner, the outer wall of the lower damping member 2 and the upper damping member 7 respectively abuts with the half-cup-shaped structure inner wall of the tension arm 4 and the base 1, and the upper damping member 7 and the lower damping member 2 are in a top and bottom center symmetry, thereby generating stable, higher, uniformly distributed and asymmetric damping to attenuate the vibration of the tensioner and increase the service life of the tensioner. The first positioning clamping block 101 abuts with one end face of the lower damping member 2, so that the first positioning clamping block 101 and the lower damping member 2 are connected head to tail, and the force can be transmitted between the first positioning clamping block 101 and the lower damping member 2. The first spring stop block 102 is located in the opposite face 180° direction of the lower damping member 2, and abuts against the lower end of the spiral spring 3 to prevent the spiral spring 3 from tilting. The outer wall 203 of the lower damping member 2 abuts with the inner wall of the second half-cup-shaped structure 402 of the tension arm 4. The lower damping member 2 is subjected to the transverse extrusion force of the spring under the action of the spring torsion force, so that the outer wall of the lower damping member 2 abuts and rubs with the inner wall of the tension arm 4 to generate damping. The second half-cup-shaped structure 402 of the tension arm 4 needs to be machined to reduce the surface roughness, so that the first outer wall 203 of the lower damping member 2 is more stable when contacting and rubbing with the second half-cup-shaped structure 402, and the service life of the lower damping member 2 is increased. In the pre-assembly state, the lower end face 405 of the tension arm 4 is placed on the upper end face of the base 1. After rotating a certain early warning angle, the tension arm 4 is pressed down, so that the lower end face 405 enters the early warning angle limiting groove 104, thereby controlling the stroke and angle of the tensioner during operation. The pulley connecting structure is provided with a rotatable pulley 8 which abuts with the engine belt. Specific embodiment two:

[0037] As Figure 5 Or Figure 6 Or Figure 7As shown, on the basis of the first embodiment, the two ends of the helical spring 3 are provided with straight edges, including the lower end straight edge 301 and the upper end straight edge 302. The damping member is in a semicircular arc horseshoe shape, and the middle of the lower damping member 2 is provided with a first spring hanging mouth straight slot 201. The lower damping member 2 is placed on the base 1, the first spring hanging mouth straight slot 201 faces upward, and the lower end straight edge 301 is sleeved into the first spring hanging mouth straight slot 201 on the lower damping member 2. The middle of the upper damping member 7 is provided with a second spring hanging mouth straight slot 701, and the upper damping member 2 is placed on the base 1, the second spring hanging mouth straight slot 701 faces downward, and the upper end straight edge 302 is sleeved into the second spring hanging mouth straight slot 701.

[0038] In the above technical solution, the second positioning clamping block 403 is attached to one end face of the upper damping member 7, so that the second positioning clamping block 403 and the upper damping member 7 are connected head to tail, and the force can be transmitted between the second positioning clamping block 403 and the upper damping member 7. The second spring stop block 404 is provided on the opposite face 180° of the upper damping member 7 on the tensioning arm 4, and abuts against the upper end of the helical spring 3 to prevent the helical spring 3 from tilting. The second outer wall 703 of the upper damping member 7 is attached to the inner wall of the first half-cup-shaped structure 103 of the base 1. The upper damping member 7 drives the helical spring 3 to twist under the action of the tensioning arm 4, so that the damping member is subjected to a transverse extrusion force of the spring, and the outer wall of the upper damping member 7 is attached to the inner wall of the base 1 to generate friction, thereby generating damping. At this time, the helical spring 3 is in a retracted state, and the second half-cup-shaped structure 402 of the tensioning arm 4 is subjected to machining treatment to reduce the surface roughness, so that the outer wall of the upper damping member 7 and the inner wall of the second half-cup-shaped structure 402 are more stable when they are in contact and friction, thereby increasing the service life of the damping member.

[0039] Further, the helical spring 3 can also be twisted by external support.

[0040] Further, the damping member is not limited to a semicircular arc horseshoe shape; the damping member can be in a "U" shape; the damping member can have a semicircular arc shape in the outer contour, and a plurality of protrusions are symmetrically arranged on the inner side of the circular arc; the damping member can have a semicircular arc shape in the outer contour, and a plurality of protrusions are asymmetrically arranged on the inner side of the circular arc; the damping member can have a multilayer structure with a semicircular arc shape in the outer contour, and protrusions are arranged between the layer structures.

[0041] Working principle: as Figure 6 or Figure 7As shown, the helical spring 3 is a helical torsion spring, the base 1 is fixed on the cover of the engine by the base bolt, when the tensioner operates to tighten the belt, the belt drive tensioning arm 4 moves in the range of the limiting groove to tighten the engine belt, when the tensioning arm 4 moves back and forth, the second positioning block 403 will exert a pushing force F1 on the second end surface 702 of the upper damping member 7, driving the upper damping member 7 to rotate with the tensioning arm 4; since the upper end straight edge 302 of the helical spring 3 is sleeved on the second spring hanging straight slot 701, when the tensioning arm 4 rotates, the helical spring 3 is driven to stretch and rotate, the number of turns increases, thereby generating a torque; in the process of rotating the helical spring 3, the upper end straight edge 302 of the helical spring 3 generates an outward pushing force F2 on the upper damping member 7, so that the second outer wall 703 of the upper damping member 7 tightly abuts against the first half-cup-shaped structure 103 of the base 1 to generate sliding friction, thereby generating a friction damping force; similarly, when the helical spring 3 rotates back, the lower end straight edge 301 of the helical spring 3 drives the lower damping member 2 to move outward to generate a pushing force F3, so that the first outer wall 203 of the lower damping member 2 tightly abuts against the second half-cup-shaped structure 402 of the tensioning arm 4 to generate sliding friction, thereby generating a friction damping force, and at the same time, the first positioning block 101 at the bottom of the base 1 generates a pushing force F4 on the first end surface 202 of the damping member, so that the damping member and the shell do not produce relative displacement.

[0042] The present application has the following beneficial effects: the upper damping member is arranged between the tensioning arm and the helical spring, the lower damping member is arranged between the base and the helical spring, through the friction of different surfaces, stable, high, uniformly distributed and asymmetric damping is generated to attenuate the vibration of the tensioner and increase the service life of the tensioner; the damping can provide larger and stable damping, so that the driving system will not fail due to damping attenuation, two damping members are placed in the center of the tensioner in one above and one below, thereby providing larger damping together; in the preloaded state, the lower end surface of the tensioning arm is placed on the upper end surface of the base, after rotating a certain warning angle, the tensioning arm is pressed down, so that the lower end surface enters the warning angle limiting groove, thereby controlling the stroke and angle of the tensioner during operation.

Claims

1. An automatic tensioner with non-surface friction dual damping, characterized in that, include: The base (1) has an opening at one end and a first semi-cup-shaped structure (103) is provided on the base (1). The main shaft (6) is coaxially installed in the base (1). The lower end of the main shaft (6) is interference-fitted with the bottom of the base (1). The main shaft (6) is provided with an axial through hole (601). Tensioning arm (4), which is provided with a second half-cup structure (402) and a pulley connection structure, and the tensioning arm (4) rotates at the opening of the base (1); The helical spring (3) is a helical torsion spring, which is coaxially sleeved on the main shaft (6); The damping component includes an upper damping component (7) and a lower damping component (2) arranged in a centrally symmetrical manner. The upper damping component (7) is disposed between the inner surface of the tension arm (4) and the helical spring (3) and rubs against the inner wall of the base (1). The lower damping component (2) is disposed between the inner surface of the base (1) and the helical spring (3) and rubs against the inner wall of the tension arm (4). When the tensioner is running, the outer wall of the lower damping member (2) is in contact with the inner wall of the tensioning arm (4). The bottom of the tensioning arm (4) is provided with a second positioning block (403) for cooperating with one end face of the upper damping member (7) and a second spring stop block (404) for preventing the helical spring (3) from tilting. When the tensioner is running, the outer wall of the upper damping member (7) is in contact with the inner wall of the base (1). The tensioning arm is provided with a second spring stop block at 180° opposite the upper damping member.

2. The automatic tensioner with non-surface friction dual damping according to claim 1, characterized in that, The base (1) is provided with a first positioning block (101) for cooperating with one end face of the lower damping member (2) and a first spring stop (102) for preventing the helical spring (3) from tilting. The first cup-shaped structure and the second cup-shaped structure form a cup-shaped structure with a certain gap, the gap being the position of the warning angle. The first spring stop is located 180° opposite to the lower damping member.

3. An automatic tensioner with non-surface friction dual damping as described in claim 1 or 2, characterized in that, The base (1) is provided with a warning angle limiting groove (104), and the second half-cup structure (402) protrudes on one side to form a lower end face (405). The warning angle limiting groove (104) and the lower end face (405) are assembled and limited.

4. The automatic tensioner with non-surface friction dual damping according to claim 1, characterized in that, The tensioning arm (4) has a rotary through hole (401) in the middle, which can rotate and be connected to the upper end of the main shaft (6). A bushing (5) is provided between the main shaft (6) and the rotary through hole (401) of the tensioning arm (4). The bushing (5) is a cylindrical ring with a wear-resistant coating on the inner side. The inner hole of the bushing (5) and the main shaft (6) are clearance fit, and the rotary through hole (401) of the tensioning arm (4) and the bushing (5) are interference fit.

5. The automatic tensioner with non-surface friction dual damping according to claim 1, characterized in that, The helical spring (3) has straight edges at both ends, including a lower straight edge (301) and an upper straight edge (302).

6. An automatic tensioner with non-surface friction dual damping according to claim 5, characterized in that, The lower damping member (2) has a first spring hanging slot (201) in the middle. The lower damping member (2) is placed on the base (1) with the first spring hanging slot (201) facing upward. The lower straight edge (301) is fitted into the first spring hanging slot (201) on the lower damping member (2).

7. An automatic tensioner with non-surface friction dual damping according to claim 5, characterized in that, The upper damping member (7) has a second spring hanging slot (701) in the middle. The upper damping member is placed on the base (1), with the second spring hanging slot (701) facing down. The upper straight edge (302) is fitted into the second spring hanging slot (701).

8. An automatic tensioner with non-surface friction dual damping according to claim 1, 2, or 5, characterized in that, The pulley connection structure is connected to the pulley (8), and the pulley (8) is mounted on the tensioning arm (4) by bearing (9), dust cover (10) and bolt (11).

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