JP4494321B2 - Valve timing adjustment device - Google Patents

Description

  The present invention relates to a valve timing adjusting device for controlling the opening / closing timing of an intake valve or an exhaust valve of an internal combustion engine such as an engine (hereinafter referred to as an engine).

  A conventional valve timing adjusting device includes a housing having a bearing portion of a camshaft, a case having a plurality of protruding shoes on the inside and forming a hydraulic chamber between the shoes, and a front cover and a rear cover that block the hydraulic chamber. A first rotating body fixed integrally and rotating integrally with the crankshaft, and a plurality of vanes that divide the hydraulic chamber into an advance hydraulic chamber and a retard hydraulic chamber, respectively, have a relative rotation by a predetermined angle within the first rotary body. The hydraulic pump of the oil pump that supplies the oil to the engine sliding portion is supplied and discharged. The relative position of the two rotating bodies is controlled.

  In the above configuration, when there is no oil pressure at the time of starting the engine, the shoe of the first rotating body and the vane of the second rotating body come into contact with each other, and the hitting sound is repeatedly generated. Therefore, a hole is formed through the shoe in the radial direction, and the lock pin housed in the hole is pressed by a coil spring inserted into the hole so that, for example, the second rotating body is positioned at the most retarded position. Engaging with an engaging recess provided on the outer peripheral surface of the second rotating body, the relative position between the first rotating body and the second rotating body is fixed to suppress the generation of sound. Then, when the hydraulic pressure from the oil tank is increased by starting the engine, the lock pin is released from the engaging recess against the pressing force of the coil spring by the oil pressure, and the first rotating body and the second rotating body rotate relative to each other. Make it possible.

  This valve timing adjusting device has a suitable timing range for each model of the internal combustion engine, for example. For this reason, the range from the most retarded valve timing to the most advanced valve timing and the allowable range of the rotational phase difference have to be changed for each internal combustion engine model. Therefore, conventionally, as described in Patent Document 1, a variable angle limiting pin is provided on a side plate of a hydraulic chamber, and a vane is brought into contact with the variable angle limiting pin. In this case, for example, the valve timing adjustment device for the internal combustion engine for high speed rotation and the valve timing adjustment device for the internal combustion engine for low speed rotation have the same size of the valve timing adjustment device and the chain sprocket and camshaft connected to the valve timing adjustment device. However, there is a need for a valve timing adjusting device that differs only in the maximum operating angle depending on the specifications of the internal combustion engine.

Japanese Patent No. 3473368

  Since the conventional valve timing adjusting device is configured as described above, in order to change the operating angle so as to suit the model of the internal combustion engine, a limiting pin for limiting the operating angle and a hole for inserting the limiting pin Processing required a step of inserting a limiting pin into the hole. For this reason, the number of parts, the number of processing points, the number of work points, etc. increased, and there was a problem that the cost was increased.

  The present invention has been made to solve the above-described problems. By merely cutting a part of the valve timing adjusting device, valve timing adjusting devices having different maximum operating angles can be made with high accuracy and at low cost. The purpose is to do.

  A valve timing adjusting device according to the present invention includes a housing having a bearing portion of a camshaft, a case in which a plurality of protruding shoes are radially formed on the inside, and a hydraulic chamber is formed between the shoes, and a front cover that closes the hydraulic chamber And a first rotating body that integrally fixes the rear cover and rotates integrally with the crankshaft, and a plurality of vanes that divide the hydraulic chamber into an advance hydraulic chamber and a retard hydraulic chamber, respectively, within a predetermined angle within the first rotary body. A second rotating body which is relatively rotatable and is integrally fixed to an intake or exhaust camshaft; hydraulic supply / discharge means capable of supplying and discharging hydraulic oil to and from the advance hydraulic chamber and the retard hydraulic chamber; When the second rotating body provided on the first rotating body rotates to the most retarded angle position or the most advanced angle position and faces the engaging recess provided on the surface of the second rotating body, the engaging force is applied by the biasing force of the biasing means. Projected into the recess A locking pin which engages, in which a said shoe or the machined portion to expand the operation range of the second rotating member by being formed cutting into either the contact surface of the vane.

  According to the present invention, the second rotation is achieved by cutting the work portion formed on either the shoe provided on the first rotating body or the contact surface of the vane provided on the second rotating body. Since it is configured to expand the range of body movement, a valve timing adjustment device suitable for internal combustion engines of different models can be manufactured at low cost with no need for new parts and simple cutting that does not require machining accuracy. Can be made separately.

  Also, when there are multiple abutment parts for shoes and vanes, valve timing adjustment suitable for internal combustion engines with different types of models is made by forming processed parts with different projecting amounts at each abutment part. The apparatus can be made at low cost by simple processing that does not require processing accuracy without requiring new parts. In this case, the change in balance due to the change in the operable range due to the cutting can be reduced by providing the workpieces having different protrusion amounts in diagonal order across the rotation shaft.

Embodiment 1 FIG.
The drawing shows the internal configuration of the valve timing adjusting apparatus according to Embodiment 1 of the present invention. FIG. 1 shows the valve along the line BB in FIG. 2 when the second rotating body is located at the most retarded position. FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 is a cross-sectional view of the valve timing adjuster when the second rotating body is positioned at the most advanced angle position. It is.

  As shown in FIGS. 1 to 3, the valve timing adjusting apparatus 1 according to the first embodiment rotates synchronously via a crankshaft (not shown) and a chain (not shown) of an engine (not shown). The first rotating body 1 and a second rotating body 3 disposed in the first rotating body 1 and fixed integrally to an end surface of an intake or exhaust camshaft (hereinafter referred to as a camshaft) 2 are schematically configured. Has been.

  The first rotating body 1 has a case 4 having a plurality of shoes 4b-1 to 4b-4 projecting radially inwardly, and a rotational driving force of the front cover 5 and the crankshaft that closes the inner space of the case 4. A rear cover 6 having a receiving sprocket 4 a on the outside is schematically configured, and is fixed integrally with the three by bolts 7.

  The second rotating body 3 includes a boss portion 10a that is integrally fastened to the end surface of the camshaft 2 by a bolt 9 via a washer 8, and a plurality of protrusions that protrude radially outward from the outer peripheral portion of the boss portion 10a. The rotor 10 includes vanes 10b-1 to 10b-4. The vanes 10 b-1 to 10 b-4 of the rotor 10 are used for rotating the rotor 10 relative to the case 4 toward the advance side with respect to the plurality of inner spaces formed by the shoes 4 b-1 to 4 b-4 of the case 4. Are divided into a plurality of advance hydraulic chambers 11 that receive the hydraulic pressure supply, and a plurality of retard hydraulic chambers 12 that receive the hydraulic supply when the rotor 10 is rotated relative to the case 4 toward the retard side. Each advance hydraulic chamber 11 communicates with a retard oil passage 13 for supplying and discharging hydraulic pressure, and each retard hydraulic chamber 12 is communicated with an advance oil passage (not shown) for supplying and discharging hydraulic pressure.

  A storage hole 15 (first hole) penetrating in the radial direction is formed in the shoe 4b-1 of the case 4. A substantially cylindrical lock pin 16, which can reciprocate along the axial direction thereof, is inserted into the storage hole 15 from the outside. Further, a substantially cylindrical hole (second hole) 4c is formed in the shoe 4b-1 in a direction intersecting with the storage hole 15 (axial direction of the rotor 10). Then, a pressing member 31 is inserted into the receiving hole so as to engage the rear end of the coil spring 18 inserted so as to press the lock pin 16 into the receiving hole 15, and the insertion direction is inserted into the circumferential surface of the pressing member 31. The engaging recess 31a formed in a direction orthogonal to the hole 4c is matched with the hole 4c, and the pin 17 is inserted into the matched hole to support the holding member 31 in order to prevent it from coming off.

  In the first embodiment, the slowest position (most retarded position) of the valve timing adjusting device is determined by the contact of the shoe 4b-1 of the first rotating body 1 and the vane 10b-1 of the second rotating body 3. The rotation of the rotor 10 causes the other surface of the vane 10b-1 to contact the shoe 4b-2, or the other shoe and the other vane to contact each other, so that the valve timing adjusting device is in the most advanced position (first highest position). Determine the advance angle position. The angle between the most retarded angle position and the most advanced angle position is the maximum operating angle of the valve timing adjusting device. In the first embodiment, there are four pairs of shoes 4b-1 to 4b-4 and vanes 10b-1 to 10b-4. A pair of shoes and vanes that contact at the most advanced angle position and the most retarded angle position are a pair. ing.

  The first embodiment is an example in which the lock pin is engaged with the engagement recess 19 on the surface of the second rotator at the position where the second rotator is most delayed with respect to the first rotator (most retarded angle position). A release oil passage 20 communicates with the storage hole 15. Processed portions 33a, 33c, and 33d having different protrusion amounts (sequentially smaller) are formed on the rotation direction surfaces (advance direction surfaces) of the vanes 10b-1, 10b-3, and 10b-4.

Next, the operation will be described.
First, when the relative position of the rotor 10 with respect to the case 4 is at the most retarded position shown in FIGS. 1 and 2, the lock pin 16 is engaged with the engagement recess 19 by the urging force of the coil spring 18 (the lock pin). Engagement state). In this state, when hydraulic pressure is supplied from the oil pump to the storage hole 15 through the release oil passage 20 as the engine starts, this hydraulic pressure is received by the step portion of the lock pin 16. For this reason, the lock pin 16 slides radially in the accommodation hole 15 against the urging force of the coil spring 18 by hydraulic pressure, and is released from the engagement recess 19. At this time, the oil on the lock pin back pressure side is discharged from the oil passage 35 to the front cover 5 side. The rotor 10 from which the lock pin 16 is released is supplied with oil into the advance hydraulic chamber 11 via the advance oil passage 13, and the oil in the retard hydraulic chamber 12 passes through the retard oil passage (not shown). As shown in FIG. 3, it is relatively rotated toward the advance side.

  In this case, the first maximum operating angle A is when the workpiece 33a of the vane 10b-1 contacts the shoe 4b-2. When an operation angle larger than the maximum operation angle A is required, the processed portion 33a of the vane 10b-1 is removed by cutting as shown in FIG. 4, and the rotating shaft is sandwiched as shown in FIG. The processed part 33c of the vane 10b-3 having a smaller protrusion than the processed part 33a on the diagonal side is brought into contact with the shoe 4b-3. The angle between the most retarded angle position and the advanced contact position thus formed is the second maximum operating angle B in the valve timing adjusting device, and the operating angle is expanded. That is, the second maximum operation angle B can be set larger than the first maximum operation angle A.

  Furthermore, when a large operating angle is required, the processed portion 33c is removed by cutting as shown in FIG. 6, and the vane 10b− having a smaller protrusion than the diagonally processed portion 33c as shown in FIG. The third maximum operation angle C larger than the second maximum operation angle B can be obtained by bringing the four processed parts 33d into contact with the shoe 4b-1.

  In this case, the complicated shape of the case 4 that is the first rotating body 1 and the rotor 10 that is the second rotating body 3 is formed by molding such as die casting, extrusion, sintering, etc. The contact surface newly formed by machining is also determined by the shape / dimension at the time of molding, and machining accuracy is not required simply by preventing the machining from contacting. Further, the number of parts does not increase, machining accuracy is not required, and the valve timing adjusting device can be made separately without cost.

  When the relative position of the rotor 10 with respect to the case 4 is the advance position, oil is supplied into the retard hydraulic chamber 12 via the retard oil passage 13, and the oil in the advance hydraulic chamber 11 is advanced. By being discharged through (not shown), it is relatively rotated to the retard side. When the relative position of the rotor 10 with respect to the case 4 is rotated to the most retarded position, the lock pin 16 is moved inwardly in the receiving hole 15 by the urging force of the coil spring 18 as shown in FIGS. To engage with the engaging recess 19.

  As described above, according to the first embodiment, the work portion formed on either the shoe provided on the first rotating body or the contact surface of the vane provided on the second rotating body is cut. Since the workable range of the second rotating body is expanded by machining, a valve timing adjustment device suitable for an internal combustion engine of a different model can be machined without requiring new parts. It can be obtained inexpensively with simple processing.

  In addition, when there are multiple abutment parts for the shoe and vane, a plurality of models can be differentiated by forming the work parts with different projecting amounts on each abutment part on the diagonal side across the rotating shaft. A valve timing adjusting device suitable for an internal combustion engine can be obtained in a balanced and inexpensive manner with simple processing that does not require processing accuracy, without requiring new parts. Further, when the work portion formed on the vane is cut, the vane has a shape protruding in the axial direction, so that the degree of freedom in selecting a processing method increases.

Embodiment 2. FIG.
In the first embodiment, a valve timing adjusting device having different maximum operating angles is obtained by cutting the processed portion 33a formed on the plurality of vanes 10b-1 or the like. In the second embodiment, the processed portion 34a is formed on the shoe 4b-2 corresponding to the vane 10b-1, and the processed portion 34a is cut to adjust the valve timing of the maximum operating angle suitable for different types of internal combustion engines. An apparatus is obtained. In FIG. 8, a processed portion 34a is formed on one shoe 4b-2, but a plurality of shoes 4b-3, 4b-4, and 4b-1 have different projection amounts (sequentially smaller). A part may be formed. For example, in the second embodiment, the processed portion 34a is formed on one shoe, but the operating angle can be further expanded by forming the processed portion on two shoes, and three shoes. By forming the part to be machined, the operating range can be expanded in three stages. Thereby, in the case of the valve timing adjusting device that forms the processed parts on the four shoes, it is possible to expand the operation range in four stages by sequentially processing the processed parts provided on the four shoes. In this case, the order of vanes or shoes for cutting the workpiece is performed in a diagonal order with the rotating shaft in between, so that fluctuations in weight balance due to cutting of the workpiece can be reduced, and valve timing adjustment Rotation variation of the device can be suppressed.

Further, when the first oil passage is in the first rotating body, the contact surface at the most retarded position is not processed, and the contact surface to be processed is always the contact surface in the same direction, for example, the advance angle of the vane. By processing the side abutment surface, the first oil passage position at the most retarded angle position can be manufactured in a stable position in the valve timing adjustment device made separately, so it becomes a structure that does not cause a difference in performance due to making separately, High accuracy.
In this case, the most retarded angle side is the locking position of the lock pin, but only the contact surface on the opposite side to the most retarded angle side, that is, the abutting surface on the most advanced angle side, is processed to create a different valve timing. The positioning of the lock pin position in the adjusting device can also be made common.

As described above, according to the second embodiment, the machining timing formed in the valve timing adjusting device suitable for a plurality of internal combustion engine models is required by removing the workpiece formed on the shoe by cutting. It can be made easily and inexpensively by simple processing.
In the first and second embodiments, it has been described that the processed portion is formed on the most advancing side contact surface and the processed portion is cut. However, the most advanced angle side is set as the lock position of the lock pin. The processed portion may be formed on the most retarded contact surface and the processed portion may be cut.

Embodiment 3 FIG.
The third embodiment shows an example of cutting a workpiece, and FIG. 9 shows a workpiece 33a which is moved in the direction of the arrow while rotating a tool 35 (tool) having a cutting blade on its peripheral surface. Is cut. Further, FIG. 10 is for cutting a workpiece by rotating a tool 36 (tool) having a cutting blade on the lower end surface in the direction of the arrow while rotating.

In the illustrated embodiment, the boss portion of the second rotating body 3 serves as a sliding surface and a seal surface of the seal, but the boss portion is provided in the cutting of the workpiece by providing the relief portion 37 in the shape before processing. It is possible to prevent a step from occurring on the sliding surface. As a result, the valve timing adjusting device having different prepared operable ranges can be slid without being caught.
In the illustrated example, the lock pin 16 is inserted into the storage hole 15 formed in the radial direction in the shoe 4 b-1 of the case 4, and the end of the lock pin is formed in the engagement recess provided on the peripheral surface of the boss portion of the rotor 10. Although the most retarded angle position is determined by engaging, the lock pin is inserted into the storage hole formed in the shoe 4b-1 of the case 4 in the axial direction, and the lock pin tip is formed in the rear cover 6. It can also be configured to determine the most retarded angle position by engaging with the recess.

Embodiment 4 FIG.
The fourth embodiment shows the internal configuration of the valve timing adjusting device that does not require a lock pin. FIG. 11 shows B′-B ′ of FIG. 12 when the second rotating body is located at the most retarded position. 12 is a longitudinal sectional view of the valve timing adjusting device along the line, FIG. 12 is a transverse sectional view taken along the line A′-A ′ of FIG. 1, and FIG. It is a cross-sectional view of the adjusting device, the same parts as in FIGS.

The first to third embodiments have a lock pin that holds the rotor 10 in the most retarded position or the most advanced position before starting the engine in order to prevent the occurrence of abnormal noise. In Embodiment 4, the lock pin is not required. For example, the lock timing pin is not provided in a valve timing adjusting device mounted on an engine that uses auxiliary power such as a motor. Even in this case, the reference position of the rotor 10 is the most retarded position.

In addition, since the rotation speed of the starter is high and hydraulic pressure is supplied to the valve timing adjusting device before starting the engine by auxiliary power, it is possible to control abnormal noise without providing a lock pin. Even in such a valve timing adjusting device that does not require a lock pin, the valve timing adjusting device suitable for an internal combustion engine of a different model by cutting a workpiece is used in Embodiments 1 to 1. It is possible to apply the same effect as that of the third embodiment.

It is a figure which shows the internal structure of the valve timing adjustment apparatus by Embodiment 1 of this invention, and is a longitudinal cross-sectional view which follows the BB line of FIG. 2 when a 2nd rotary body is located in the most retarded angle position. It is a cross-sectional view which follows the AA line of FIG. It is a longitudinal cross-sectional view of the valve timing adjustment apparatus when a 2nd rotary body is located in the most advanced angle position. It is a figure which shows the internal structure of the valve timing adjustment apparatus by Embodiment 2 of this invention, and is a side view when a 2nd rotary body is located in the most retarded angle position. It is a cross-sectional view when processing is performed to obtain the second maximum operating angle and the second rotating body is positioned at the most retarded angle position. FIG. 6 is a cross-sectional view showing a state where the second rotating body is rotated to the most advanced position in FIG. 5. It is a cross-sectional view when processing is performed to obtain a third maximum operating angle and the second rotating body is positioned at the most retarded angle position. FIG. 8 is a cross-sectional view showing a state where the second rotating body is rotated to the most advanced position in FIG. 7. It is a perspective view which shows the state which cuts a to-be-processed part. It is a perspective view which shows the state which cuts a to-be-processed part. It is a perspective view which shows the other state which cuts a to-be-processed part. It is a figure which shows the internal structure of the valve timing adjustment apparatus by Embodiment 4 of this invention, and is a longitudinal cross-sectional view which follows the B'-B 'line of FIG. 2 when a 2nd rotary body is located in the most retarded angle position. is there. It is a cross-sectional view which follows the A'-A 'line of FIG. It is a longitudinal cross-sectional view of the valve timing adjustment apparatus when a 2nd rotary body is located in the most advanced angle position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st rotary body, 2 camshaft, 3 2nd rotary body, 4 case, 4a sprocket, 4b shoe, 4b-1 hole (2nd hole), 5 front cover, 6 rear cover, 7, 9 bolt, 8 washer, 10 rotor, 10a boss, 10b vane, 11 advance hydraulic chamber, 12 retard hydraulic chamber, 13 advance oil passage, 14 retard oil passage, 15 storage hole (first hole), 16 lock pin , 17 shaft, 18 coil spring, 19 engagement hole, 20 release oil passage.

Claims (6)

A first rotating body that integrally rotates with a crankshaft having a plurality of protruding shoes on the inside and forming a hydraulic chamber between the shoes;
A plurality of vanes that divide the hydraulic chamber into an advance hydraulic chamber and a retard hydraulic chamber each have a radial shape, can be relatively rotated by a predetermined angle within the first rotating body, and are integrally fixed to an intake or exhaust camshaft. A second rotating body;
Hydraulic supply / discharge means capable of supplying and discharging hydraulic oil to the advance hydraulic chamber and the retard hydraulic chamber;
A valve timing adjusting device comprising: a work portion that is formed on one of the contact surfaces of the shoe and the vane in the relative rotation direction and that changes the operable range of the second rotating body by cutting.   When the second rotating body provided in the first rotating body rotates to the most retarded position or the most advanced angle position and faces the engaging recess provided on the surface of the second rotating body, the engaging force is applied by the biasing force of the biasing means. 2. The valve timing adjusting device according to claim 1, further comprising a lock pin that protrudes and engages with the recess. 2. The valve timing adjusting device according to claim 1, wherein the workpieces provided on the contact surfaces in the plurality of relative rotation directions have different protrusion amounts in the operation angle direction . Workpieces provided on a plurality of contact surfaces in the relative rotation direction are alternately provided diagonally across the rotation axis in order of cutting the workpiece and changing the maximum operating angle of the valve timing adjusting device. the valve timing adjusting apparatus according to claim 1, wherein the a. The contact surface of the vane of the second rotating body that contacts the shoe having the lock pin of the first rotating body is used as a reference surface of the narrow operating angle specification and the wide operating angle specification. 4. The valve timing adjusting device according to claim 1. The contact surface between the shoe of the first rotating body and the vane of the second rotating body is a contact surface having different operating angle directions in the narrow operating angle specification and the wide operating angle specification. 4. The valve timing adjusting device according to claim 1.

Images