JP6609603B2 - Chain drive tensioner spring force control mechanism - Google Patents

Description

  The present invention relates to the field of tensioners. More particularly, the present invention relates to a chain drive tensioner spring force control mechanism.

  In general, in a timing chain for a valve drive device of an internal combustion engine, a camshaft chain used for the camshaft-camshaft drive device and a balancer chain are provided with a chain in order to take the slack of the chain and apply tension to the chain. The tensioner used on the relaxation side of the.

  During operation, the tensioner piston pushes the chain to maintain chain tension. In operation, when chain tension increases due to chain span resonance, high loads from the chain act on the tensioner piston, causing the piston to retract into the tensioner housing.

  Since the spring force of a chain drive tensioner is sufficient to cope with the worst case operating condition of the tensioner system, the spring force is often too high for most operating conditions. A tensioner's effectiveness and overall system behavior and efficiency could be improved if the spring force of the tensioner can be varied depending on the operating conditions, taking into account the wear and elongation that occurs in the chain during the life of the chain. .

  An inward force acting to push the piston into the housing generates fluid pressure in a hydraulic chamber formed by the cylindrical bore of the housing and the movable sleeve, and the movable sleeve acts against the piston via a piston spring. A tensioner that applies outward force and opposes inward force.

1 shows a schematic of a tensioner of a first embodiment of a passive tensioner system that tensions a new chain. An outline of a tensioner that tensions a wear chain without a high load is shown. An outline of a tensioner that tensions a worn chain with high load is shown. Fig. 4 shows a schematic of a tensioner of a passive tensioner system of a second embodiment for tensioning a new chain. Fig. 4 shows a schematic of a tensioner of a passive tensioner system of a third embodiment for tensioning a new chain. The passive tensioner system of the fourth embodiment uses a chamber formed between the outer peripheral flange of the movable sleeve and the bore flange of the housing to maintain the position of the movable sleeve relative to the piston to tension the new chain. An outline of the tensioner is shown. A passive tensioner of a fifth embodiment that uses a chamber formed between the bore flange of the housing and a cutout on the outer periphery of the movable sleeve to maintain the position of the movable sleeve relative to the piston to tension the new chain An outline of the system tensioner is shown. The tensioner of the sixth embodiment of the passive tensioner system that uses a chamber formed between the outer peripheral flange of the movable sleeve and the bore of the housing to maintain the position of the movable sleeve relative to the piston to tension the new chain The outline of is shown. Seventh implementation using a chamber formed between the outer flange of the movable sleeve supplied by the spool valve and the bore flange of the housing to maintain the position of the movable sleeve relative to the piston to tension the new chain. 1 shows a schematic of a tensioner of a passive tensioner system of the form. An eighth is to use a chamber formed between the outer flange of the movable sleeve and the bore of the housing supplied by the spool valve and accumulator to maintain the position of the movable sleeve relative to the piston to tension the new chain. The outline of the tensioner of the passive tensioner system of an embodiment is shown. FIG. 10 shows a schematic of a tensioner of a ninth embodiment of an active tensioner system that uses feedback control to move and maintain a movable sleeve relative to a piston to tension a new chain. FIG. FIG. 14 shows a schematic of a tensioner of an active tensioner system of a tenth embodiment that uses feedback control to move a movable sleeve relative to a piston to tension a new chain. FIG.

  1a-8 show a tensioner system that uses passive control to maintain the position of the movable sleeve relative to the piston. Passive control is defined as a system that does not use feedback to control the position of the movable sleeve relative to the tensioner piston. In contrast, FIGS. 9 and 10 are active control systems in which real-time feedback of engine components and / or the movable sleeve itself is used to adjust the position of the sleeve.

  The tensioner system of the present invention includes a tensioner of a closed loop chain drive system (described in more detail below) used in internal combustion engines. It may be used in a closed loop power transmission system between the drive shaft and at least one camshaft, or may be used in a balance shaft system between the drive shaft and the balance shaft. The tensioner system may also include an oil pump and may be used with a fuel pump drive. Furthermore, the tensioner system of the present invention may also be used with a belt drive.

  1a-1c show a first embodiment tensioner that applies tension under various chain conditions. FIG. 1a tensions a new chain, FIG. 1b tensions a wear chain without high load, and FIG. 1c tensions the wear chain under high load.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. The piston bore 2a has an interior having a first diameter portion D1 and a second diameter portion D2, and the second diameter portion D2 is larger than the first diameter portion D1.

  A movable sleeve 18 is received in the bore 2 a of the housing 2. The movable sleeve 18 is hollow and forms a pressure chamber 16 having a pressure P1 with the bore 2a of the housing 2, the inner diameter portion 17 of the hollow movable sleeve 18, ie, the hollow interior, and the interior 3a of the piston 3.

  A sleeve spring 5 is present in the bore 2 a and is received in the inner diameter portion 17 of the movable sleeve 18, and the first end 5 a of the sleeve spring 5 contacts the bottom surface 24 of the inner flange 22 of the movable sleeve 18. The second end portion 5b contacts the bottom portion 2c of the bore 2a. The sleeve spring 5 provides a biasing force and reduces the control force required to maintain the movable sleeve 18 in the desired position with respect to the piston 3.

  The movable sleeve 18 has an outer peripheral flange 20, which increases the diameter of the movable sleeve 18 to be approximately equal to the diameter of the second diameter portion D2, but the flange 20 is the second diameter portion D2 of the bore 2a. Allowing the fluid chamber 14 to form between the bottom surface 27 of the outer peripheral flange 20 and the second diameter portion D2 of the bore 2a. The fluid chamber 14 is in fluid communication with the oil pressure supply 7 via a supply line 12 that includes a check valve 10. Supply 7 supplies fluid to fluid chamber 14 to compensate for any possible leakage. The check valve 10 prevents the fluid in the fluid chamber 14 from flowing back into the supply unit 7. Note that fluid pressure is not supplied to the region between the upper surface 29 of the outer peripheral flange 20 and the bore 2a.

  At least a part of the movable sleeve 18 in front of the outer peripheral flange 20 is slidably received in the hollow piston 3. Also present in the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the interior 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 26 of the inner flange 22 of the movable sleeve 18. A through hole 25 is present in the inner flange 22 and allows fluid from the inlet supply line 6 to the interior 3 a of the piston 3 and the upper surface 26 of the inner flange 22 of the movable sleeve 18.

  In order to provide oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom of the bore 2a (not shown). The supply 7 that provides fluid to the fluid chamber 14 may be the same as the supply that provides fluid to the inlet supply line 6. Alternatively, the supply that provides fluid to the inlet supply line 6 may be different from the supply 7 that is in fluid communication with the fluid chamber 14. Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  Referring to FIG. 1a, when the tensioner is tensioning a new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, The chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2 to urge the span of the closed loop chain.

  Referring to FIG. 1b, when the tensioner is tensioning the wear chain in the absence of a high load, during operation, fluid is drawn from the inlet supply line 6, possibly via an inlet check valve (not shown). , Supplied to the hydraulic chamber 16, pressurizes the hydraulic chamber 16, urges the piston 3 outward from the housing 2 in addition to the spring force from the piston spring 4, and urges the span of the closed loop chain. Since the chain is worn, it is necessary to urge the piston 3 further outward from the housing 2 in order to properly tension the chain. When urging the piston 3 outward from the housing 2, a larger amount of fluid is required to increase the spring force, so that part of the fluid supplied to the hydraulic chamber 16 leaks into the fluid chamber 14 and is movable. The sleeve 18 is moved outward from the housing 2. It should be noted that the movable sleeve 18 is moved outwardly by the oil from the supply 7 rather than the oil from the hydraulic chamber 16.

  Referring to FIG. 1c, during high chain loads, when the tensioner is tensioning the wear chain, during operation, a high force causes the piston 3 to move from the piston position shown in FIG. Push inward toward. Inward forces and movement of the piston 3 are resisted by the fluid in the fluid chamber 14. This is because the check valve 10 of the supply line 12 prevents fluid from exiting the fluid chamber 14 and substantially pressurizes the fluid chamber 14. Due to the pressurization of the fluid chamber 14, the inner flange 22 of the movable sleeve 18 applies an outward force to the piston 3 via the piston spring 4 and opposes the inward force. When the high load is removed from the piston 3, the chamber 14 is substantially depressurized, the supply 7 supplies fluid via the check valve 10 and supplies fluid to the fluid chamber 14 to fill the fluid chamber 14, The movement of the sleeve 18 relative to the piston 3 is supplemented, and the position of the sleeve 18 relative to the piston 3 is maintained.

  By the movement of the movable sleeve 18, the second end 4 b of the piston spring 4 is moved, and the piston 3 is urged outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  A seal (not shown) is between the outer peripheral flange 20 and the movable sleeve 18, and the second diameter portion D2 of the bore 2a, the first diameter portion D1 of the bore or any other in the tensioner as required. It may exist between places.

  The tensioner hydraulic stiffness is generated by the tensioner pressure chamber 16 and hydraulic chamber 14 and substantially reduces the inward movement of the piston 3 and movable sleeve 18 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 2 shows a tensioner of a passive tensioner system that uses supply pressure to move a movable sleeve 33 received by the hollow piston 3 of the second embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. The piston bore 2a has an interior having a first diameter portion D1 and a second diameter portion D2, and the second diameter portion D2 is larger than the first diameter portion D1.

  A hollow movable sleeve 33 is received in the bore 2 a of the housing 2. A hollow fixed sleeve 30 is received in the hollow movable sleeve 33. Within the hollow fixed sleeve 30 is a sleeve spring 5. The first end 5 a of the sleeve spring 5 is in contact with the bottom surface 36 of the inner flange 34 of the movable sleeve 33, and the second end 5 b of the sleeve spring 5 is in contact with the bottom surface 32 of the inner flange 31 of the hollow fixed sleeve 30, or When the flange 31 is not present, it contacts the bottom of the bore 29a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 33 in a desired position relative to the piston 3. The pressure chamber 16 is formed between the inner diameter portion 38 of the fixed sleeve 30, the inner diameter portion 17 inside the hollow of the hollow movable sleeve 33, and the inner portion 3 a of the piston 3.

  The movable sleeve 33 has a diameter, which is approximately equal to the diameter of the second diameter portion D2, but allows the movable sleeve 33 to slide within the bore 2a. A fluid chamber 37 is formed between the bottom 2 c of the bore 2 a, the fixed sleeve 30, and the bottom end face 39 of the movable sleeve 33. The fluid chamber 37 is in fluid communication with the oil pressure supply 7 via the supply line 12 including the check valve 10. The supply 7 supplies fluid to the fluid chamber 37 to compensate for any possible leakage. The check valve 10 prevents the fluid in the fluid chamber 37 from flowing back into the supply unit 7. Note that no fluid pressure is supplied to the area between the piston 3, the movable sleeve 33 and the second diameter portion D2 of the bore 2a.

  At least a part of the movable sleeve 33 is slidably received in the hollow piston 3. Also present in the hollow piston 3 is a piston spring 4 that urges the piston 3 outwardly from the housing 2. The piston spring 4 has a first end 4 a that contacts the inner portion 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 35 of the inner flange 34 of the movable sleeve 33. A through hole 25 exists in the inner flange 34 and allows fluid from the supply line 6 to the interior 3 a of the piston and the upper surface 35 of the inner flange 34 of the movable sleeve 33.

  In addition to the inlet supply line 6, an inlet check valve may be present at the bottom of the bore 2a to provide oil pressure to the pressure chamber 16 (not shown). The supply 7 that provides fluid to the fluid chamber 37 may be the same as the supply that provides fluid to the inlet supply line 6. Alternatively, the supply that supplies fluid to the inlet supply line 6 may be different from the supply 7 that is in fluid communication with the fluid chamber 37. Furthermore, a discharge part or a pressure relief valve (not shown) may be present in the hollow piston 3.

  When the tensioner is tensioning the new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve (not shown), and the hydraulic chamber 16 And in addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2, and the span of the closed loop chain is urged in the same manner as in FIG. 1a.

  In operation without tension, when the tensioner is tensioning the worn chain, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, during operation, The hydraulic chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is biased outward from the housing 2 and the span of the closed loop chain is biased. Since the chain is worn, it is necessary to urge the piston 3 further outward from the housing 2 in order to properly tension the chain. When the piston 3 is urged outward from the housing 2, a larger amount of fluid is required to increase the spring force, so that part of the fluid supplied to the hydraulic chamber 16 is a movable sleeve 33 and a fixed sleeve 30. And leak into the fluid chamber 37 between the housing bore 2a and move the movable sleeve 33 outwardly from the housing 2 as in FIG. 1b. Note that the movable sleeve is moved outwardly by the oil from the supply 7 rather than the oil from the hydraulic chamber 16.

  During operation, when the tensioner is tensioning the worn chain during a high chain load, during operation, a high force will force the piston 3 inward from the piston position shown in FIG. Press to. Inward force and movement of the piston 2 are resisted by the fluid in the fluid chamber 37. This is because the check valve 10 of the supply line 12 prevents fluid from exiting the fluid chamber 37 and substantially pressurizes the chamber 37. Due to the pressurization of the fluid chamber 37, the inner flange 34 of the movable sleeve 33 applies an outward force to the piston 3 via the piston spring and opposes the inward force. When the high load is removed from the piston 3, the chamber 37 is substantially depressurized and the supply 7 supplies fluid via the check valve 10 and supplies fluid to the fluid chamber 37 to fill the fluid chamber 37, The movement of the sleeve 33 relative to the piston 3 is supplemented, and the position of the sleeve 33 relative to the piston 3 is maintained.

  The movement of the movable sleeve 33 moves the second end 4 b of the piston spring 4 and biases the piston 3 outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  A seal (not shown) is located between the movable sleeve 33 and the second diameter portion D2 of the bore 2a and the first diameter of the second diameter portion D2 and the bore D1 or anywhere else in the tensioner as required. May be present between

  The tensioner hydraulic stiffness is generated by the tensioner pressure chamber 16 and the hydraulic chamber 37 and substantially allows the inward movement of the piston 3 and the movable sleeve 33 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 3 shows a tensioner of a passive tensioner system that uses supply pressure to move the movable sleeve 40 that receives the hollow piston 3 of the third embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. A movable sleeve 40 is received in the bore 2 a of the housing 2. The movable sleeve 40 has a first opening 46 a defined by the upper inner diameter portion 46 and the upper surface 43 of the central inner flange 41, and a second opening 45 a defined by the bottom inner diameter portion 45 and the bottom surface 42 of the central inner flange 41. Have A through hole 47 in the center inner flange 41 connects the first opening 46 a to the second opening 45 a of the movable sleeve 40. The upper surface 48 of the movable sleeve 40 is exposed to atmospheric pressure.

  It is the hollow piston 3 that is received within the first opening 46 a of the movable sleeve 40 defined by the upper inner diameter portion 46 and the upper surface 43 of the central inner flange 41. Within the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the inner portion 3 a of the hollow piston 3, and a second end 4 b that contacts the upper surface 43 of the center inner flange 41 of the movable sleeve 40.

  Receiving within the second opening 45 a of the movable sleeve 40 defined by the bottom inner diameter portion 45 and the bottom surface 42 of the central inner flange 41 is a hollow fixed sleeve 30. Within the hollow fixed sleeve 30 is a sleeve spring 5. The first end 5 a of the sleeve spring 5 is in contact with the bottom surface 42 of the central inner flange 41 of the movable sleeve 40, and the second end 5 b of the sleeve spring 5 is in contact with the bottom surface 32 of the inner flange 31 of the hollow fixed sleeve 30. . The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 40 in a desired position relative to the piston 3. The pressure chamber 16 is located between the inner portion 38 of the fixed sleeve 30 or, if no flange 31 is present, the bottom of the bore, the inner diameter portion 17 of the second opening 45a of the movable sleeve 40, and the interior 3a of the piston 3. It is formed. A through hole 47 is present in the central inner flange 41 and allows fluid from the inlet supply line 6 to the interior 3 a of the piston and the upper surface 43 of the central inner flange 41 of the movable sleeve 40.

  The fluid chamber 37 is formed between the bottom of the bore 2 a, the fixed sleeve 30, and the bottom end surface 39 of the movable sleeve 40. The fluid chamber 37 is in fluid communication with the oil pressure supply 7 via the supply line 12 including the check valve 10. The check valve 10 prevents the fluid in the fluid chamber 37 from flowing back into the supply unit 7.

  In order to provide the oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom 2c of the bore 2a (not shown). The supply 7 that provides fluid to the fluid chamber 37 may be the same as the supply that provides fluid to the inlet supply line 6. Alternatively, the supply that supplies fluid to the inlet supply line 6 may be different from the supply 7 that is in fluid communication with the fluid chamber 37. Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  When the tensioner is tensioning the new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, pressurizing the hydraulic chamber 16, In addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2 and the span of the closed loop chain is urged in the same manner as in FIG. 1a.

  In operation without tension, when the tensioner is tensioning the worn chain, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, during operation, The hydraulic chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is biased outward from the housing 2 and the span of the closed loop chain is biased. Since the chain is worn, it is necessary to urge the piston 3 further outward from the housing 2 in order to properly tension the chain. When the piston 3 is urged outward from the housing 2, a larger amount of fluid is required to increase the spring force, so that part of the fluid supplied to the hydraulic chamber 16 is part of the movable sleeve 33 and the fixed sleeve 30. And the movable sleeve 40 is moved outwardly from the housing as in FIG. 1b. Note that the movable sleeve is moved outwardly by the oil from the supply 7 rather than the oil from the hydraulic chamber 16.

  During operation, when the tensioner is tensioning the worn chain during high chain loads, during operation, a high force will force the piston 3 inward from the piston position shown in FIG. Push. Inward force and piston movement are resisted by the fluid in the fluid chamber 37. This is because the check valve 10 of the supply line 12 prevents fluid from exiting the fluid chamber 37 and substantially pressurizes the fluid chamber 37. Due to the pressurization of the fluid chamber 37, the inner flange 41 of the movable sleeve 40 applies an outward force to the piston 3 via the piston spring 4 and opposes the inward force.

  When the high load is removed from the piston 3, the chamber 37 is substantially depressurized and the supply 7 supplies fluid via the check valve 10 and supplies fluid to the fluid chamber 37 to fill the fluid chamber 37, The movement of the sleeve 40 relative to the piston 3 is supplemented, and the position of the sleeve 40 relative to the piston 3 is maintained.

  The movement of the movable sleeve 40 moves the second end 4b of the piston spring 4 and urges the piston 3 outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  A seal (not shown) may be present between the bore 2a and the movable sleeve 40 or anywhere else in the tensioner as required.

  The tensioner hydraulic stiffness is generated by the tensioner pressure chamber 16 and the hydraulic chamber 37 and substantially allows the inward movement of the piston 3 and the movable sleeve 40 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 4 shows a tensioner of a passive tensioner system that uses supply pressure to move a movable sleeve received by the hollow piston 3 of the fourth embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. The piston bore 2a has an interior having a first diameter portion D1 and a second diameter portion D2, and the second diameter portion D2 is larger than the first diameter portion D1. A bore flange 150 separates the second diameter portion D2 of the bore 2a that receives the piston 3 and another second diameter portion D2 of the bore that receives the outer peripheral flange 141 of the movable sleeve 140.

  A movable sleeve 140 is received in the bore 2 a of the housing 2. The movable sleeve 140 is hollow and forms the pressure chamber 16 together with the bore 2 a of the housing 2, the inner diameter portion 17 of the hollow movable sleeve 140, and the interior 3 a of the piston 3. A sleeve spring 5 is present in the bore 2 a and is received in the inner diameter portion 17 of the movable sleeve 140, the first end 5 a of the spring 5 contacts the bottom surface 147 of the inner flange 145 of the movable sleeve 140, and the spring 5 The two ends 5b are in contact with the bottom 2c of the bore 2a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 140 in a desired position relative to the piston 3.

  The movable sleeve 140 has an outer peripheral flange 141 having a top surface 142 having a region A2 and a bottom surface 143 having a region A1. The area A2 on the top surface 142 is smaller than the area A1 on the bottom surface 143. A first fluid chamber 58 is formed between the top surface 142 of the outer peripheral flange 141 and the bottom surface 152 of the bore flange 150, and a second fluid chamber 57 is formed between the bottom surface 143 of the outer peripheral flange 141 and another wall 73 of the second diameter portion D2. Formed between.

  The first fluid chamber 58 is preferably connected to the supply 7 via a line 55 having a check valve 53, and the second fluid chamber 57 is also preferably connected via a line 56 having a check valve 54. 7 is connected. The check valves 53 and 54 prevent the fluid in the fluid chambers 58 and 57 from flowing back into the supply unit 7. Supply 7 supplies fluid to fluid chambers 58 and 57 to compensate for possible leakage.

  At least a part of the movable sleeve 140 in front of the outer peripheral flange 141 is slidably received in the hollow piston 3. Also present in the hollow piston 3 is a piston spring 4 which urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the inner portion 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 146 of the inner flange 145 of the movable sleeve 140. A through hole 144 is present in the inner flange 145 to allow fluid from the inlet supply line 6 to the interior 3 a of the piston and the upper surface 146 of the inner flange 145 of the movable sleeve 140.

  In order to provide the oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom 2c of the bore 2a (not shown). The supply 7 that provides fluid to the fluid chambers 57, 58 may be the same as the supply that provides fluid to the inlet supply line 6. Alternatively, the supply that supplies fluid to the inlet supply line 6 may be different from the supply 7 that is in fluid communication with the fluid chambers 57, 58. Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  When the tensioner is tensioning the new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, pressurizing the hydraulic chamber 16, In addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2 and the span of the closed loop chain is urged in the same manner as in FIG. 1a.

  In operation without tension, when the tensioner is tensioning the worn chain, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, during operation, The hydraulic chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is biased outward from the housing 2 and the span of the closed loop chain is biased. Since the chain is worn, it is necessary to urge the piston 3 further outward from the housing 2 in order to properly tension the chain. When urging the piston 3 outward from the housing 2, a larger amount of fluid is required to increase the spring force, so that a portion of the fluid supplied to the hydraulic chamber 16 is part of the movable sleeve 140 and the housing. Leak into the fluid chambers 57, 58 between the bores 2a. It should be noted that the movable sleeve 140 is moved outwardly by the oil from the supply 7 rather than the oil from the hydraulic chamber 16. Since the bottom surface 143 of the outer peripheral flange 141 has a region A1 larger than the region A2 of the upper surface 142 of the outer peripheral flange 141, it is necessary for the chamber 57 to move the movable sleeve 140 outward from the housing as in FIG. The fluid pressure is less than the fluid pressure required by chamber 58 to move movable sleeve 140 in the opposite direction.

  During operation, when the tensioner is tensioning the worn chain during a high chain load, during operation, a high force will force the piston 3 inward from the piston position shown in FIG. Press to. Inward force and movement of the piston 3 are resisted by the fluid in the fluid chamber 57. This is because the check valve 54 of the supply line 56 prevents fluid from exiting the fluid chamber 57 and substantially pressurizes the chamber 57. Further, since the area A1 of the bottom surface 143 of the outer peripheral flange 141 is larger than the area A2 of the upper surface 142 of the outer peripheral flange 141, the inner flange 145 of the movable sleeve 33 is “pushed” by the pressurization of the fluid chamber 57, that is, the movable sleeve. 140 is moved outward from the housing 2 and an outward force is applied to the piston 3 via the piston spring 4 to oppose the inward force. When a high load is removed from the piston 3, the fluid chamber 57 is substantially depressurized and the supply 7 supplies fluid via the check valve 54 and supplies fluid to the fluid chamber 57 to fill the fluid chamber 57. The movement of the sleeve 140 relative to the piston 3 is supplemented, and the position of the sleeve 140 relative to the piston 3 is maintained.

  By the movement of the movable sleeve 140, the second end 4b of the piston spring 4 is moved, and the piston 3 is urged outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  Note that fluid chamber 58 is pressurized when fluid chamber 57 is depressurized. The movable sleeve 140 is moved by filling the fluid chamber 57 with the fluid from the supply unit 7. Movement of the movable sleeve 140 beyond or above the movement necessary to maintain the position of the piston 3 with respect to the chain is resisted by the fluid in the fluid chamber 58. This is because the check valve 53 of the supply line 55 prevents fluid from exiting the fluid chamber 58 and substantially pressurizes the chamber 58. When the load is removed from the sleeve, the chamber 58 is depressurized and the supply 7 supplies fluid via the check valve 53, supplying fluid to the fluid chamber 58, filling the chamber 58, and the sleeve 140 relative to the piston 3. It compensates for the movement and maintains the position of the sleeve 140 relative to the piston despite other forces acting on the sleeve.

  A seal (not shown) may exist between the bore 2a and the movable sleeve 140 or anywhere else in the tensioner as required.

  The tensioner hydraulic stiffness is generated by the tensioner pressure chamber 16 and the fluid chambers 57, 58, and substantially translates the inward movement of the piston 3 and movable sleeve 140 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 5 shows a tensioner of a passive tensioner system that uses supply pressure to move a movable sleeve received by a piston of a fifth embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. A movable sleeve 163 is received in the bore 2 a of the housing 2. The movable sleeve 163 is hollow and forms the pressure chamber 16 together with the bore 2 a of the housing 2, the inner diameter portion 169 of the hollow movable sleeve 163, and the interior 3 a of the piston 3.

  A sleeve spring 5 is present in the bore 2 a and is received in the inner diameter portion 169 of the movable sleeve 163, the first end 5 a of the spring 5 contacts the bottom surface 166 of the inner flange 164 of the movable sleeve 163, and the spring 5 The two ends 5b are in contact with the bottom 2c of the bore 2a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 163 in a desired position relative to the piston 3.

  There is a peripheral notch 168 along the outer periphery of the movable sleeve 163. A notch 168 in the movable sleeve 163 slidably receives the bore flange 160. The bore flange 160 has a top surface 161 having a region A1 and a bottom surface 162 having a region A2. The area A1 of the upper surface 161 of the bore flange 160 is larger than the area A2 of the bottom surface 162 of the bore flange 160.

  A first fluid chamber 58 is formed between the upper surface 161 of the bore flange 160 and the notch 168 in the movable sleeve 163, and a second fluid chamber 57 is provided between the bottom surface 162 of the bore flange 160 and the notch 168 in the movable sleeve 163. It is formed between the surfaces. The first fluid chamber 58 is preferably connected to the supply 7 via a line 55 having a check valve 53, and the second fluid chamber 57 is also preferably connected via a line 56 having a check valve 54. 7 is connected. The check valves 53 and 54 prevent the fluid in the fluid chambers 58 and 57 from flowing back into the supply unit 7. Supply 7 provides fluid to fluid chambers 57, 58 to compensate for possible leakage.

  At least a portion of the movable sleeve 163 in front of the notch 168 is slidably received in the hollow piston 3. Also present in the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the interior 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 165 of the inner flange 164 of the movable sleeve 163. A through hole 144 is present in the inner flange 164 to allow fluid from the inlet supply line 6 to the interior 3 a of the piston and the upper surface 165 of the inner flange 164 of the movable sleeve 163.

  In order to provide oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom of the bore 2a (not shown). The supply 7 that provides fluid to the fluid chambers 57, 58 may be the same as the supply that provides fluid to the inlet supply line 6. Alternatively, the supply that supplies fluid to the inlet supply line 6 may be different from the supply 7 that is in fluid communication with the fluid chambers 57, 58. Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  When the tensioner is tensioning the new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, pressurizing the hydraulic chamber 16, In addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2 and the span of the closed loop chain is urged in the same manner as in FIG. 1a.

  In operation without tension, when the tensioner is tensioning the worn chain, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, during operation, The hydraulic chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is biased outward from the housing 2 and the span of the closed loop chain is biased. Since the chain is worn, it is necessary to urge the piston 3 further outward from the housing 2 in order to properly tension the chain. When urging the piston 3 outward from the housing 2, a larger amount of fluid is required to increase the spring force, so that a portion of the fluid supplied to the hydraulic chamber 16 can be moved between the movable sleeve 163 and the housing. Leak into the fluid chambers 57, 58 between the bores 2a. Since the top surface 161 of the bore flange 160 has a region A1 that is larger than the region A2 of the bottom surface 162 of the bore flange 160, the chamber 58 is more than the chamber 57 to move the movable sleeve 163 outward from the housing, as in FIG. Requires less fluid pressure. It should be noted that the movable sleeve 163 is moved outwardly by the oil from the supply 7 rather than the oil from the hydraulic chamber 16.

  During operation, when the tensioner is tensioning the worn chain during a high chain load, during operation, a high force will force the piston 3 inward from the piston position shown in FIG. Press to. Inward forces and movement of the piston 3 are resisted by the fluid in the fluid chamber 58. This is because the check valve 53 of the supply line 55 prevents the fluid from exiting the fluid chamber 58 and substantially pressurizes the fluid chamber 58. Furthermore, because the area A1 of the upper surface 161 of the bore flange 160 is larger than the area A2 of the bottom surface 162 of the bore flange 160, the pressurization of the fluid chamber 58 causes the inner flange 164 of the movable sleeve 163 to be “pushed”, ie, the housing 2 , Outwardly, applying an outward force to the piston 3 via the piston spring 4 to oppose the inward force. When the high load is removed from the piston 3, the fluid chamber 58 is substantially depressurized and the supply 7 supplies fluid via the check valve 53 and supplies fluid to the fluid chamber 58 to fill the fluid chamber 58. The movement of the sleeve 163 relative to the piston 3 is compensated, and the position of the sleeve 163 relative to the piston 3 is maintained.

  By the movement of the movable sleeve 163, the second end 4b of the piston spring 4 is moved, and the piston 3 is urged outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  Note that fluid chamber 57 is pressurized when fluid chamber 58 is depressurized. The movable sleeve 163 is moved by filling the fluid chamber 58 with fluid from the supply unit 7. Movement of the movable sleeve 163 beyond or above the movement necessary to maintain the position of the piston 3 with respect to the chain is resisted by the fluid in the fluid chamber 57. This is because the check valve 54 of the supply line 56 prevents fluid from exiting the fluid chamber 57 and substantially pressurizes the chamber 57. When the load is removed from the sleeve, the fluid chamber 57 is depressurized and the supply 7 supplies fluid via the check valve 54, supplies fluid to the fluid chamber 57, fills the chamber 57, and sleeve 163 for the piston 3. And maintains the position of the sleeve 163 relative to the piston despite other forces acting on the sleeve.

  A seal (not shown) may exist between the bore 2a and the movable sleeve 163 or anywhere else in the tensioner as required.

  The tensioner hydraulic stiffness is generated by the tensioner chamber 16 and the fluid chambers 57, 58, and substantially reduces the inward movement of the piston 3 and the movable sleeve 163 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 6 shows a passive tensioner system that uses an internal pressure region and flange pressure to move a movable sleeve received by the piston of the sixth embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. A movable sleeve 80 is received in the bore 2 a of the housing 2. The movable sleeve 80 has a first opening 89 a defined by the upper inner diameter portion 89 and the upper surface 81 of the central flange 82, and a second opening 96 a defined by the bottom inner diameter portion 96 and the bottom surface 83 of the central inner flange 82. Have. A through hole 97 in the center inner flange 82 connects the first opening 89 a to the second opening 96 a of the movable sleeve 80. The upper surface 98 of the movable sleeve 80 is exposed to the atmospheric pressure of the engine.

  It is the hollow piston 3 that is received within the first opening 89 a of the movable sleeve 80 defined by the upper inner diameter portion 89 and the upper surface 81 of the central inner flange 82. Within the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the inner portion 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 81 of the center inner flange 82 of the movable sleeve 80.

  It is the sleeve spring 5 that is received within the second opening 96 a of the movable sleeve 80 defined by the bottom inner diameter portion 96 and the bottom surface 83 of the central inner flange 82. The first end 5a of the sleeve spring 5 is in contact with the bottom surface 83 of the central flange 82 of the movable sleeve 80, and the second end 5b of the sleeve spring 5 is in contact with the bottom 2c of the bore 2a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 80 in a desired position relative to the piston 3. Upper inner diameter portion 89 of sleeve 80 in which pressure chamber 16 is formed, bottom inner diameter portion 96 of sleeve 80, housing bore 2a and piston interior 3a. A through hole 97 is present in the central inner flange 81 and allows fluid from the inlet supply line 6 to flow from the second opening 96a to the first opening 89a.

  In order to provide oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom of the bore 2a (not shown). The supply 7 that provides fluid to the fluid chambers 94, 95 may be the same as the supply that provides fluid to the inlet supply line 6. Alternatively, the supply that supplies fluid to the inlet supply line 6 may be different from the supply 7 that is in fluid communication with the fluid chambers 94, 95. Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  The movable sleeve 80 has an outer peripheral flange 84 that is substantially equal to the width of the second diameter portion D2, but that the flange 84 slides within the second diameter portion D2 of the bore 2a, and the first fluid chamber. 95 and the second fluid chamber 94 can be formed. The first fluid chamber 95 is preferably connected to the supply 7 via a line 93 having a check valve 92, and the second fluid chamber 94 is also preferably connected via a line 91 having a check valve 90. 7 is connected. The check valves 92 and 90 prevent the fluid in the fluid chambers 94 and 95 from flowing back into the supply unit 7. Supply 7 provides fluid to fluid chambers 94, 95 as needed to compensate for leakage. The outer diameter of the movable sleeve 80 below the outer peripheral flange 84 is received by the first diameter portion D1 of the bore 2a, and the second diameter portion D2 is larger than the first diameter portion D1.

  When the tensioner is tensioning the new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, pressurizing the hydraulic chamber 16, In addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2 and the span of the closed loop chain is urged in the same manner as in FIG. 1a.

  In operation without tension, when the tensioner is tensioning a worn chain, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, during operation, The hydraulic chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is biased outward from the housing 2 and the span of the closed loop chain is biased. Since the chain is worn, it is necessary to bias the piston 3 further outward from the housing 2 in order to properly tension the chain. When urging the piston 3 outwardly from the housing 2, a larger amount of fluid is required to increase the spring force, so that a portion of the fluid supplied to the hydraulic chamber 16 can be moved from the movable sleeve 80 and the housing bore. 2a leaks into the fluid chambers 94, 95 and the fluid pressure in the chamber 16 on the bottom surface 99 of the sleeve 80 and the bottom surface 83 of the central inner flange 82 moves the sleeve 80 outward from the housing, similar to FIG. 1a. Let It should be noted that the movable sleeve is moved outwardly by the oil from the supply rather than the oil from the hydraulic chamber 16.

  During operation, when the tensioner is tensioning the worn chain during a high chain load, during operation, a high force will force the piston 3 inward from the piston position shown in FIG. Press to. Inward force and piston movement are resisted by the fluid in the fluid chamber 94. This is because the check valve 90 of the supply line 91 prevents the fluid from exiting the fluid chamber 94 and substantially pressurizes the chamber 94. Due to the pressurization of the fluid chamber 94 in addition to the pressure applied to the bottom surface 99 of the movable sleeve 80, the central inner flange 82 of the movable sleeve 80 applies an outward force to the piston 3 via the piston spring 4 and opposes the inward force. . When the high load is removed from the piston 3, the chamber 94 is substantially depressurized and the supply 7 supplies fluid via the check valve 10 and supplies fluid to the fluid chamber 94 to fill the fluid chamber 94, The movement of the sleeve 80 relative to the piston 3 is supplemented, and the position of the sleeve 80 relative to the piston 3 is maintained.

  By the movement of the movable sleeve 80, the second end 4b of the piston spring 4 is moved, and the piston 3 is urged outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  Note that fluid chamber 95 is pressurized when fluid chamber 94 is depressurized. The movable sleeve 80 is moved by filling the fluid chamber 94 with the fluid from the supply unit 7. Movement of the movable sleeve beyond or above the movement necessary to maintain the position of the piston 3 relative to the chain is resisted by the fluid in the fluid chamber 95. This is because the check valve 92 of the supply line 93 prevents fluid from exiting the fluid chamber 95 and substantially pressurizes the chamber 95. When the load is removed from the sleeve 80, the chamber 95 is depressurized and the supply 7 supplies fluid via the check valve 92, supplies fluid to the fluid chamber 95, fills the chamber 95, and sleeve 80 for the piston 3. And maintains the position of the sleeve 80 relative to the piston despite other forces acting on the sleeve.

  A seal (not shown) may exist between the bore 2a and the movable sleeve 80 or anywhere else in the tensioner as required.

  The tensioner hydraulic stiffness is generated by the tensioner pressure chamber 16 and the fluid chambers 94, 95, and provides substantial inward movement of the piston 3 and movable sleeve 80 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 7 shows a tensioner of the passive tensioner system of the seventh embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. The piston bore 2a has an interior having a first diameter portion D1 and a second diameter portion D2, and the second diameter portion D2 is larger than the first diameter portion D1. A bore flange 52 separates the second diameter portion D2 of the bore 2a that receives the piston 3 and another second diameter portion D2 of the bore that receives the outer peripheral flange 20 of the movable sleeve 18.

  A movable sleeve 18 is received in the bore 2a of the housing. The movable sleeve 18 is hollow and forms a pressure chamber 16 together with the bore 2 a of the housing 2, the inner diameter portion 17 of the hollow movable sleeve 18, and the inside of the piston 3. A sleeve spring 5 is present in the bore 2 a and is received in the inner diameter portion 17 of the movable sleeve 18, the first end 5 a of the spring 5 contacts the bottom surface 24 of the inner flange 22 of the movable sleeve 18, and the spring 5 The two ends 5b are in contact with the bottom 2c of the bore 2a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 18 in a desired position relative to the piston 3.

  The movable sleeve 18 has an outer peripheral flange 20 having an upper surface 29 and a bottom surface 27. The outer peripheral flange 20 separates the second diameter portion D2 of the housing 2 into first and second fluid chambers 58,57. A first fluid chamber 58 is formed between the top surface 29 of the outer peripheral flange 20 and the bottom surface 51 of the bore flange 52, and a second fluid chamber 57 is formed between the bottom surface 27 of the outer peripheral flange 20 and another wall 73 of the second diameter portion D2. Formed between.

  The first fluid chamber 58 is connected to the supply unit 7 via the line 101 and the control valve 108. The second fluid chamber 57 is connected to the supply unit 7 via the line 100 and the control valve 108. Supply unit 7 supplies fluid to fluid chambers 57 and 58 to compensate for leakage from the chamber alone. The control valve 108, preferably a spool valve, includes a spool 109 having at least two cylindrical lands 109a, 109b slidably received within the bore 106. The bore 106 may be in the tensioner housing 2 or may be located away from the engine tensioner housing. One end of the spool contacts the spring 110, and the spring 110 biases the spool in the first direction.

  At least a part of the movable sleeve 18 in front of the outer peripheral flange 20 is slidably received in the hollow piston 3. Also present in the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the inner portion 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 26 of the inner flange 22 of the movable sleeve 18. A through hole 47 is present in the inner flange 22 and allows fluid from the inlet supply line 6 to the interior 3 a of the piston and the upper surface 26 of the inner flange 22 of the movable sleeve 18.

  In order to provide oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom of the bore 2a (not shown). The supply 7 that provides fluid to the fluid chambers 57, 58 may be the same as the supply that provides fluid to the inlet supply line 6. Alternatively, the supply that provides fluid to the inlet supply line 6 may be different from the supply 7 that is in fluid communication with the fluid chambers 57, 58. Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  When the tensioner is tensioning the new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, pressurizing the hydraulic chamber 16, In addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2 and the span of the closed loop chain is urged in the same manner as in FIG. 1a.

  In operation without tension, when the tensioner is tensioning the worn chain, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, during operation, The hydraulic chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is biased outward from the housing 2 and the span of the closed loop chain is biased. Since the chain is worn, it is necessary to urge the piston 3 further outward from the housing 2 in order to properly tension the chain. When urging the piston 3 outwardly from the housing 2, a larger amount of fluid is required to increase the spring force, so that a portion of the fluid supplied to the hydraulic chamber 16 can be moved to the movable sleeve 18 and the bore of the housing. Leak into the fluid chambers 57, 58 between 2a and move the movable sleeve 18 outwardly from the housing as in FIG. 1b.

  During operation, when the tensioner is tensioning the worn chain during high chain loads, during operation, a high force will force the piston 3 inward from the piston position shown in FIG. Push. Inward force and movement of the piston 3 are resisted by the fluid in the fluid chamber 57. This is because the spring force from the spring 110 of the spool valve 108 places the land 109a in place with respect to the line 100, preventing fluid from exiting the fluid chamber 57 and substantially pressurizing the chamber 57. Due to the pressurization of the fluid chamber 57, the central inner flange 22 of the movable sleeve 40 applies an outward force to the piston 3 via the piston spring 4 and opposes the inward force. When the high load is removed from the piston 3, the chamber 57 is substantially depressurized, and the supply unit 7 supplies fluid to the fluid chamber 57 via the spool valve 108 to compensate for the movement of the sleeve 40 relative to the piston 3. Maintain the position of the sleeve 40 with respect to.

  By the movement of the movable sleeve 18, the second end 4 b of the piston spring 4 is moved, and the piston 3 is urged outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  Note that fluid chamber 58 is pressurized when fluid chamber 57 is depressurized. The movable sleeve 18 is moved by filling the fluid chamber 57 with the fluid from the supply unit 7. Movement of the movable sleeve 18 beyond or above the movement necessary to maintain the position of the piston 3 relative to the chain is resisted by the fluid in the fluid chamber 58. This is because the spool valve 108 prevents fluid from exiting the fluid chamber 58 and substantially pressurizes the chamber 58. When the load is removed from the sleeve, the chamber 58 is depressurized and the supply 7 supplies fluid through the spool 108, supplies fluid to the fluid chamber 58, fills the chamber 58, and moves the sleeve 18 relative to the piston 3. Compensates and maintains the position of the sleeve 18 relative to the piston despite other forces acting on the sleeve.

  A seal (not shown) may exist between the bore 2a and the movable sleeve 18 or anywhere else in the tensioner as required.

  The tensioner hydraulic stiffness is generated by the tensioner chamber 16 and the pressure chambers 57, 58, and substantially reduces the inward movement of the piston 3 and the movable sleeve 40 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 8 is an alternative embodiment of FIG. 7 in which the control valve 108 is in fluid communication with the accumulator 114. The accumulator 114 is also in fluid communication with the pressure chamber 16 formed by the bore 2 a of the housing 2, the inner diameter portion 17 of the hollow movable sleeve 18 and the interior 3 a of the piston 3 via a check valve 125. The accumulator 114 stores or accumulates fluid from the pressure chamber 16 and supplies it to the fluid chambers 57, 58 in the event of a leak.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. The piston bore 2a has an interior having a first diameter portion D1 and a second diameter portion D2, and the second diameter portion D2 is larger than the first diameter portion D1. A bore flange 52 separates the second diameter portion D2 of the bore 2a that receives the piston 3 and another second diameter portion D2 of the bore that receives the outer peripheral flange 20 of the movable sleeve 18.

  A movable sleeve 18 is received in the bore 2a of the housing. The movable sleeve 18 is hollow and forms a pressure chamber 16 with the bore 2 a of the housing 2, the inside of the piston 3 and the inner diameter portion 17 of the hollow movable sleeve 18. A sleeve spring 5 is present in the bore 2 a and is received in the inner diameter portion 17 of the movable sleeve 18, the first end 5 a of the spring 5 contacts the bottom surface 24 of the inner flange 22 of the movable sleeve 18, and the spring 5 The two ends 5b are in contact with the bottom 2c of the bore 2a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 18 in a desired position relative to the piston 3.

  The movable sleeve 18 has an outer peripheral flange 20 having an upper surface 29 and a bottom surface 27. The outer peripheral flange 20 separates the second diameter portion D2 of the housing 2 into first and second fluid chambers 58,57. The first fluid chamber 58 is formed between the top surface 29 of the outer peripheral flange 20 and the bottom surface 51 of the bore flange 52, and the second fluid chamber 57 is formed with the bottom surface 27 of the outer peripheral flange 20 and another wall 73 of the second diameter portion D2. Formed between.

  The first fluid chamber 58 is connected to the accumulator 114 via line 101, control valve 108, and line 112. Second fluid chamber 57 is connected to accumulator 114 via line 100, control valve 108, and line 112. The accumulator 114 supplies fluid to the chambers 57, 58 for the purpose of compensation due to leakage only. The control valve 108, preferably a spool valve, includes a spool 109 having at least two cylindrical lands 109 a, 109 b slidably received within the bore 106. The bore 106 may be in the tensioner housing 2 or may be located away from the engine tensioner housing. One end of the spool contacts the spring 110, and the spring 110 biases the spool valve in the first direction.

  At least a part of the movable sleeve 18 in front of the outer peripheral flange 20 is slidably received in the hollow piston 3. Also present in the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the inner portion 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 26 of the inner flange 22 of the movable sleeve 18. A through hole 47 is present in the inner flange 22 and allows fluid from the inlet supply line 6 to the interior 3 a of the piston and the upper surface 26 of the inner flange 22 of the movable sleeve 18.

  In order to provide oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom of the bore 2a (not shown). Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  When the tensioner is tensioning the new chain, during operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, pressurizing the hydraulic chamber 16, In addition to the spring force from the piston spring 4, the piston 3 is urged outward from the housing 2 and the span of the closed loop chain is urged in the same manner as in FIG. 1a.

  In operation without tension, when the tensioner is tensioning the worn chain, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, during operation, The hydraulic chamber 16 is pressurized, and in addition to the spring force from the piston spring 4, the piston 3 is biased outward from the housing 2 and the span of the closed loop chain is biased. Since the chain is worn, it is necessary to urge the piston 3 further outward from the housing 2 in order to properly tension the chain. When urging the piston 3 outwardly from the housing 2, a larger amount of fluid is required to increase the spring force, so that a portion of the fluid supplied to the hydraulic chamber 16 can be moved to the movable sleeve 18 and the bore of the housing. Leak into the fluid chambers 57, 58 between 2a and move the movable sleeve 18 outwardly from the housing as in FIG. 1b.

  During operation, when the tensioner is tensioning the worn chain during high chain loads, during operation, a high force will force the piston 3 inward from the piston position shown in FIG. Push. Inward force and piston movement are resisted by the fluid in fluid chamber 57. This is because the spring force from the spring 110 of the spool valve 108 places the land 109a in place with respect to the line 100, preventing fluid from exiting the fluid chamber 57 and substantially pressurizing the chamber 57. Due to the pressurization of the fluid chamber 57, the central inner flange 22 of the movable sleeve 40 applies an outward force to the piston 3 via the piston spring 4 and opposes the inward force. When the high load is removed from the piston 3, the chamber 57 is substantially depressurized and the accumulator 114 supplies fluid to the fluid chamber 57 via the spool valve 108 to fill the fluid chamber 57 and move the sleeve 40 relative to the piston 3. Make up.

  The movement of the movable sleeve 40 moves the second end 4b of the piston spring 4 and urges the piston 3 outward from the housing 2. The spring force acting on the piston 3 is therefore variable, and the piston 3 continuously tensions the chain even when the chain is worn and extended.

  Note that fluid chamber 58 is pressurized when fluid chamber 57 is depressurized. The movable sleeve 40 is moved by filling the fluid chamber 57 with the fluid from the supply unit 7. Movement of the movable sleeve 40 beyond or above the movement necessary to maintain the position of the piston 3 with respect to the chain is resisted by the fluid in the fluid chamber 58. This is because the spool valve 108 prevents fluid from exiting the fluid chamber 58 and substantially pressurizes the chamber 57. When the load is removed from the piston 3, the fluid chamber 58 is depressurized and the fluid chamber 57 is pressurized.

  A seal (not shown) may exist between the bore 2a and the movable sleeve 40 or anywhere else in the tensioner as required.

  The tensioner hydraulic stiffness is generated by the tensioner chamber 16 and the pressure chambers 57, 58, and substantially reduces the inward movement of the piston 3 and the movable sleeve 40 toward the housing 2 when the chain span is under load. To prevent.

  FIG. 9 shows an active tensioner control system of the ninth embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. The piston bore 2a has an interior having a first diameter portion D1 and a second diameter portion D2, and the second diameter portion D2 is larger than the first diameter portion D1. A bore flange 52 separates the second diameter portion D2 of the bore 2a that receives the piston 3 from another second diameter portion D2 of the bore that receives the outer peripheral flange 20 of the movable sleeve 18 via the check valve 125.

  A movable sleeve 18 is received in the bore 2 a of the housing 2. The movable sleeve 18 is hollow and forms a pressure chamber 16 with the bore 2 a of the housing 2, the interior 3 a of the piston 3 and the inner diameter portion 17 of the hollow movable sleeve 18. A sleeve spring 5 is present in the bore 2 a and is received in the inner diameter portion 17 of the movable sleeve 18, the first end 5 a of the spring 5 contacts the bottom surface 24 of the inner flange 22 of the movable sleeve 18, and the spring 5 The two ends 5b are in contact with the bottom 2c of the bore 2a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 18 in a desired position relative to the piston 3.

  The movable sleeve 18 has an outer peripheral flange 20 having an upper surface 29 and a bottom surface 27. The outer peripheral flange 20 separates the second diameter portion D2 of the housing 2 into first and second fluid chambers 58,57. The first fluid chamber 58 is formed between the top surface 29 of the outer peripheral flange 20 and the bottom surface 51 of the bore flange 50, and the second fluid chamber 57 is formed with the bottom surface 27 of the outer peripheral flange 20 and another wall 73 of the second diameter portion D2. Formed between.

  First fluid chamber 58 is in fluid communication with accumulator 114 via line 101, control valve 108, and line 112. Second fluid chamber 57 is in fluid communication with accumulator 114 via line 100, control valve 108, and line 112. The accumulator 114 is also preferably in fluid communication with the pressure chamber 16 formed by the bore 2 a of the housing 2 and the inner diameter portion 17 of the hollow movable sleeve 18.

  The control valve 108, preferably a spool valve, has at least two cylindrical lands 109 a, 109 b slidably received in a bore 106 that can block or allow fluid from the accumulator 114 to the fluid chambers 57, 58. A spool 109 is included. The bore 106 may be in the tensioner housing 2 or may be located away from the engine tensioner housing. One end of the control valve 108 contacts the actuator 116. In this embodiment, the actuator 116 is a position setting actuator or a linear actuator in which the actuator sets a specific position of the control valve 108. In an alternative embodiment, the actuator 116 may be a force actuator where the force is on one side of the control valve. Note that if the actuator 116 is a force actuator, the spring may be on the opposite side of the control valve affected by the actuator 116.

  The actuator is controlled by a controller 118 that receives a setpoint input 122 from a setpoint algorithm or map 124. Controller 118 also receives position feedback 120 of tensioner movable sleeve 18 via a sensor (not shown). The setpoint algorithm or map 124 receives inputs from different engine parameters 126 such as but not limited to cam timing, engine speed, throttle, temperature, age, and tensioner position.

  At least a part of the movable sleeve 18 in front of the outer peripheral flange 20 is slidably received in the hollow piston 3. Also present in the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the interior 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 26 of the inner flange 22 of the movable sleeve 18. A through hole 47 is present in the inner flange 22 and allows fluid from the inlet supply line 6 to the interior 3 a of the piston 3.

  In order to provide oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom of the bore 2a (not shown). Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  In operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, adding to the hydraulic chamber 16 and the chamber 9 formed in the inner part 3a of the piston. The piston is biased outwardly from the housing 2 together with the spring force from the piston spring 4 to bias the span of the closed loop chain.

  A sensor (not shown) provides position feedback 120 of the movable sleeve 18 to the controller 118. The controller 118 compares the movable sleeve position feedback to a setpoint algorithm based on different engine parameters 126 or a setpoint 122 from the map 124.

  When the position of the movable sleeve 18 is equal to the set point 122, the control valve 108 is not moved or actuated and the lands 109a, 109b block fluid flow from the accumulator 114 to the fluid chambers 57, 58. Furthermore, since no fluid is added or removed from the fluid chambers 57, 58, the position of the movable sleeve 18 relative to the piston 3 and the housing bore 2a is maintained.

  If the position of the movable sleeve 18 is not equal to the set point 122, the actuator 116 actuates the control valve 108 to a position where fluid flows from the accumulator 114 to the fluid chambers 57, 58 and moves the movable sleeve 18 through the piston. 3 and the housing bore 2a. The movement of the movable sleeve 18 moves the position of the second end 4b of the piston spring 4 in contact with the upper surface 26 of the inner flange 22 of the movable sleeve 18, and the piston 3 is urged outward from the housing 2 so that the chain or Contact with the span of a belt (not shown). Since the second end 4b of the piston spring 4 that urges the piston 3 outward from the housing 2 is movable, the spring force acting on the piston 3 is variable, and the piston 3 is worn when the chain is worn and extended. Even apply tension to the chain continuously.

  The movement of the movable sleeve 18 moves the second end 4b of the piston spring 4 that urges the piston 3 outward from the housing 2, so that the spring force acting on the piston 3 is variable. Continuously tensions the chain even when it wears and stretches.

  The tensioner hydraulic stiffness generated by the tensioner chamber 16 and the fluid chambers 57 and 58, and the inward movement of the piston 3 and the movable sleeve 18 toward the housing 2 substantially when the chain span is under load. To prevent.

  A seal (not shown) may exist between the bore 2a and the movable sleeve 40 or anywhere else in the tensioner as required.

  10 is an active control tensioner system of the tenth embodiment.

  The tensioner includes a housing 2 having a piston bore 2a extending in the axial direction. A movable sleeve 80 is received in the bore 2 a of the housing 2. The movable sleeve 80 has a first opening 89 a defined by the upper inner diameter portion 89 and the upper surface 82 of the central inner flange 81, and a second opening 96 a defined by the bottom inner diameter portion 96 and the bottom surface 83 of the central inner flange 81. Have A through hole 97 in the center inner flange 81 connects the first opening 89 a to the second opening 96 a of the movable sleeve 80. The movable sleeve 80 also has an upper surface 98.

  It is the hollow piston 3 that is received within the first opening 89 a of the movable sleeve 80 defined by the upper inner diameter portion 89 and the upper surface 82 of the central inner flange 81. Within the hollow piston 3 is a piston spring 4 that urges the piston 3 outward from the housing 2. The piston spring 4 has a first end 4 a that contacts the inner portion 3 a of the hollow piston 3 and a second end 4 b that contacts the upper surface 82 of the center inner flange 81 of the movable sleeve 80.

  Accepted within the second opening of the movable sleeve 80 defined by the bottom inner surface 96 and the bottom surface 83 of the central inner flange 81 is the sleeve spring 5. The first end 5a of the sleeve spring 5 is in contact with the bottom surface 83 of the central inner flange 81 of the movable sleeve 80, and the second end 5b of the sleeve spring 5 is in contact with the bottom of the bore 2a. The sleeve spring 5 provides a biasing force that reduces the control force required to maintain the movable sleeve 80 in a desired position relative to the piston 3. A pressure chamber 16 is formed between the first and second openings 89 and 96 of the movable sleeve 80, the bore 2 a and the interior 3 a of the piston 3. A through hole 97 is present in the central inner flange 81 and allows fluid from the inlet supply line 6 to the interior 3 a of the piston and the upper surface 82 of the central inner flange 81 of the movable sleeve 80.

  In order to provide the oil pressure to the pressure chamber 16, not only the inlet supply line 6 but also an inlet check valve may be present at the bottom 2c of the bore 2a (not shown). Furthermore, a discharge port or a pressure relief valve (not shown) may be present in the hollow piston 3.

  The movable sleeve 80 has an outer peripheral flange 84 that is substantially equal to the width of the second diameter portion D2, but that the flange 84 slides within the second diameter portion D2 of the bore 2a and the first fluid. A chamber 95 and a second fluid chamber 94 can be formed. First fluid chamber 95 is connected to accumulator 114 via line 101, control valve 108, and line 112. Second fluid chamber 94 is connected to accumulator 114 via line 100, control valve 108, and line 112. The accumulator 114 is also preferably in fluid communication with the pressure chamber 16 formed by the bore 2 a of the housing 2 and the bottom inner surface 96 a of the second opening 96 of the movable sleeve 80 via a check valve 125.

  The control valve 108, preferably a spool valve, has at least two cylindrical lands 109a, 109b slidably received in a bore 106 that can block or allow fluid from the accumulator 114 to the fluid chambers 94, 95. A spool 109 is included. The bore 106 may be in the tensioner housing 2 or may be located away from the engine tensioner housing. One end of the control valve 108 contacts the actuator 116. In this embodiment, the actuator 116 is a position setting actuator or a linear actuator in which the actuator sets a specific position of the control valve. In an alternative embodiment, the actuator 116 may be a force actuator where the force is on one side of the control valve. Note that if the actuator 116 is a force actuator, the spring may be on the opposite side of the control valve affected by the actuator 116.

  The actuator position is controlled by a controller 118 that receives a setpoint input 122 from a setpoint algorithm or map 124. Controller 118 also receives position feedback 120 of tensioner movable sleeve 80 via a sensor (not shown). The setpoint algorithm or map 124 receives inputs from different engine parameters 126 such as but not limited to cam timing, engine speed, throttle, temperature, age, and tensioner position.

  In operation, fluid is supplied from the inlet supply line 6 to the hydraulic chamber 16, possibly via an inlet check valve, pressurizing the hydraulic chamber 16, and with the spring force from the piston spring 4, the piston is moved into the housing 2. Energize outward from, and energize the span of the closed-loop chain.

  A sensor (not shown) provides position feedback 120 of the movable sleeve 80 to the controller 118. The controller 118 compares the movable sleeve position feedback to a setpoint algorithm based on different engine parameters 126 or a setpoint 122 from the map 124.

  When the position of the movable sleeve 80 is equal to the set point 122, the control valve 108 is not moved or actuated, and the lands 109a, 109b block fluid flow from the accumulator 114 to the fluid chambers 94,95. Furthermore, since no fluid is added or removed from the fluid chambers 94, 95, the position of the movable sleeve 80 relative to the piston 3 and the housing bore 2a is maintained.

  If the position of the movable sleeve 80 is not equal to the set point 122, the actuator causes the control valve 108 to be actuated to a position where fluid flows from the accumulator 114 to the fluid chambers 94, 95 and moves the movable sleeve 80 through the piston 3. And moved relative to the housing bore 2a. Due to the movement of the movable sleeve 80, the position of the second end 4b of the piston spring 4 that contacts the upper surface 81 of the central inner flange 81 of the movable sleeve 80 is moved, and the piston 3 is urged outward from the housing 2, and the chain Or it contacts the span of a belt (not shown). Since the second end 4b of the piston spring 4 that urges the piston 3 outward from the housing 2 is movable, the spring force acting on the piston 3 is variable, and the piston 3 is worn when the chain is worn and extended. Even apply tension to the chain continuously.

  The movement of the movable sleeve 80 moves the second end 4b of the piston spring 4 that urges the piston 3 outward from the housing 2, so that the spring force acting on the piston 3 is variable. Continuously tensions the chain even when it wears and stretches.

  The tensioner hydraulic stiffness generated by the tensioner chamber 16 and the fluid chambers 94 and 95, and the inward movement of the piston 3 and the movable sleeve 80 toward the housing 2 substantially when the chain span is under load. To prevent.

  A seal (not shown) may exist between the bore 2a and the movable sleeve 80 or anywhere else in the tensioner as required.

  Thus, it will be understood that the embodiments of the invention described herein are merely examples of the application of the principles of the present invention. References to details of the described embodiments herein are not intended to limit the scope of the claims, which are listed in their own right which are considered essential to the invention.

Claims (5)

A tensioner of a passive tensioner system for tensioning a chain or belt having a chain span,
A housing having a cylindrical bore having a first portion and a second portion, wherein the first portion has a diameter smaller than the diameter of the second portion;
A hollow piston including a body having an open end and a closed end, and a hollow interior having an inner diameter;
A hollow movable sleeve including a hollow body having an interior having an inner diameter, the first and second portions being received by the cylindrical bore of the housing, and an inner flange at the end of the second portion. A hollow movable sleeve, wherein the inner flange has a top surface and a bottom surface,
Said hollow piston and said hollow movable sleeve is disposed coaxially in said cylindrical bore of said housing, as a result, the hollow piston or one of the hollow movable sleeve, the hollow piston or the other bore of the hollow movable sleeve Accepted by
The tensioner is
A piston spring received in the hollow interior of the hollow piston for urging the hollow piston outward from the hollow movable sleeve, the first end being in contact with the inner surface of the closed end of the hollow piston A piston spring having a portion and a second end contacting the upper surface of the inner flange of the hollow movable sleeve;
A biasing spring received in the hollow body of the cylindrical bore of the housing and the hollow body of the hollow movable sleeve for biasing the hollow movable sleeve outward from the housing, the hollow movable sleeve A biasing spring having a first end contacting the bottom surface of the inner flange and a second end;
Said interior of said hollow body of the hollow movable sleeve, and the said hollow interior of the hollow piston, are formed by the said cylindrical bore of said housing, first hydraulic chamber having a first fluid input,
A second hydraulic pressure chamber formed by the cylindrical bore of the housing and the hollow movable sleeve, so that an inward force acting to push the hollow piston into the housing is A second hydraulic chamber that generates fluid pressure in the pressure chamber, causes the hollow movable sleeve to apply an outward force to the hollow piston via the piston spring, and opposes the inward force; Including tensioner.   The second hydraulic chamber is formed by a bore flange of the cylindrical bore and a notch in the hollow movable sleeve, and the second hydraulic chamber is in fluid communication with a supply through a check valve. The tensioner according to claim 1. A tensioner of an active tensioner system for tensioning a chain or belt having a chain span,
A housing having a cylindrical bore having a first portion and a second portion, wherein the first portion has a diameter smaller than the diameter of the second portion;
A hollow piston including a body having an open end and a closed end, and a hollow interior having an inner diameter;
A hollow movable sleeve including a hollow body having an interior with an inner diameter, the first and second portions received by the cylindrical bore of the housing, and a flange at the end of the second portion, the upper surface And a hollow movable sleeve having a flange having a bottom surface and a peripheral flange between the first portion and the second portion having a top surface and a bottom surface and received by the cylindrical bore of the housing;
Said hollow piston and said hollow movable sleeve is disposed coaxially in said cylindrical bore of said housing, as a result, the hollow piston or one of the hollow movable sleeve, the hollow piston or the other bore of the hollow movable sleeve Accepted by
The tensioner is
A piston spring received in the hollow interior of the hollow piston for urging the hollow piston outward from the hollow movable sleeve, the first end being in contact with the inner surface of the closed end of the hollow piston A piston spring having a portion and a second end contacting the upper surface of the flange of the hollow movable sleeve;
Wherein the hollow movable sleeve from said housing for urging outwardly a said bore and said hollow interior biasing spring received in the hollow movable sleeve of the housing, the said flange of said hollow movable sleeve A biasing spring having a first end in contact with the bottom surface and a second end;
A pressure chamber formed by the hollow interior of the hollow piston and the bore of the housing and having a first fluid input;
A first hydraulic chamber formed by the cylindrical bore of the housing and the upper surface of the outer peripheral flange of the hollow movable sleeve and in fluid communication with a supply;
It said cylindrical bore of said housing, and wherein the hollow movable sleeve is formed by said bottom surface of the outer peripheral flange, a second hydraulic pressure chamber in fluid communication with the supply unit,
A control valve having an output coupled to the first and second hydraulic chambers and an input coupled to the supply;
Setpoints determined by engine variables and setpoint algorithms;
An actuator for actuating the control valve controlled by a movable sleeve position feedback;
Wherein the actuator, the first hydraulic chamber fluid from the supply unit to move the hollow movable sleeve to vary the outward force exerted on the hollow piston via the piston spring or the second hydraulic chamber A tensioner that moves the control valve to send to the tensioner.   The tensioner of claim 3, wherein the actuator is a linear actuator.   The tensioner according to claim 3, wherein the actuator is a force actuator.

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