JP4535932B2 - Engine valve gear - Google Patents

Description

  More specifically, the present invention relates to a plurality of transmission members arranged adjacent to each other to transmit a cam lift to a valve, and to select connection / disconnection between the plurality of transmission members. Therefore, the present invention relates to a valve operating apparatus for an engine having a connection switching device composed of a plurality of pins that both hydraulically move to a connected position and move to a non-connected position.

  There is provided a valve operating apparatus with a variable operation characteristic mechanism in which a plurality of rocker arms for transmitting a cam lift to a valve are arranged side by side on a common shaft and the adjacent rocker arms are connected with pins. It is known (see Patent Document 1).

  The connection switching device used in this operating characteristic variable mechanism is adapted to the spring force of the coil spring by applying hydraulic pressure to the other end of the pin that maintains the home position by the spring force of the coil spring acting on one end thereof. The pin is moved against. According to this, in order to move the pin from the home position, a high hydraulic pressure capable of pushing and compressing the coil spring has to be applied, so the capacity of the hydraulic pump must be set high.

In order to enable the pin to operate even at a low hydraulic pressure, the spring constant of the coil spring must be set low. However, if this is done, the return response to the home position will be reduced. Therefore, it is conceivable to switch the hydraulic pressure applied to both ends of the pin in the axial direction, that is, to drive the pin both ways hydraulically (see Patent Document 2).
Japanese Patent No. 3299366 Japanese Patent Laid-Open No. 11-141322

  However, in order to configure the pin so that it can be hydraulically driven in both directions, two hydraulic supply paths are required for one set of connection switching devices. For example, one oil path provided in the rocker arm shaft is disconnected. The area must be reduced. If the cross-sectional area of the oil passage is reduced, the flow resistance of the hydraulic oil is increased, so that the responsiveness is lowered. This effect becomes more prominent because the oil passages increase as the number of switching stages increases. Increasing the diameter of the rocker arm shaft in order to ensure the cross-sectional area of the oil passage leads to an increase in the overall size of the valve operating device and an increase in the peripheral speed of the rotating part of the rocker arm. It's hard to say.

  The present invention has been devised in order to eliminate such disadvantages of the prior art, and its main object is to provide a valve operating system for an engine provided with a connection switching device that drives a pin bidirectionally hydraulically. The purpose of the present invention is to configure the connection switching device so as to suppress a decrease in responsiveness.

In order to solve such problems, claim 1 of the present invention provides at least three transmission members (first to fourth rocker arms 6a to 6a) arranged adjacent to each other to transmit cam lifts having different characteristics to the valve. 6d) and a plurality of pins (first and second pins 13a and 13b, fifth to seventh) arranged on the same axis at the time of connection in order to select connection / disconnection between the transmission members arranged adjacent to each other. Two connection switching devices (first and third connection switching devices 9a and 9c) that have pins 13e to 13g and that hydraulically move the plurality of pins to the connection position and to the non-connection position. For each of the connection switching devices, both end surfaces of the plurality of pins are connected to separate hydraulic pressure supply passages controlled to be opened and closed by electromagnetic valves, and are used as pressure receiving surfaces. The surface areas of each other Not allowed, and commonly a hydraulic supply path for connecting to the pressure receiving surface of the side pressure-receiving area is small in the hydraulic supply passage and the other of the connecting switching device that connects to the pressure receiving surface of the side pressure-receiving area is greater in one connection switching device ( The third hydraulic pressure supply passage 10c) is characterized.
Further, Claim 2 of the present invention, the valve operating system for an engine according to claim 1, for at least one of said two connecting switching device, hydraulic pressure supply to be connected to the pressure receiving surface of the receiving area is larger side The cross-sectional area of the passage (second hydraulic pressure supply path 10b) is larger than the cross-sectional area of the hydraulic pressure supply path (third hydraulic pressure supply path 10c) connected to the pressure receiving surface on the side where the pressure receiving area is small. did.

According to such a configuration of claim 1 of the present invention, even if the same hydraulic pressure is applied to both ends of the connection switching device, it can be driven to one side, so that, for example, two sets of connection switching devices are supplied with three hydraulic pressures. It is possible to control individually on the road. Thereby, it is possible to increase the cross-sectional area of each hydraulic pressure supply path by reducing the number of hydraulic pressure supply paths, and to suppress a decrease in responsiveness.
According to the configuration of claim 2 of the present invention, the pressure receiving area is large, and the cross-sectional area of the hydraulic pressure supply passage to the side where a larger amount of hydraulic oil is required can be increased without impairing the layout efficiency of the oil passage Responsiveness can be improved.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

(Valve operated device)
1 and 2 are schematic configuration diagrams of a valve gear constructed according to the present invention. An engine cylinder head 1 is provided with a pair of exhaust valves 2a and 2b attached to each cylinder. These exhaust valves 2a and 2b include five cams 4a to 4e formed integrally with the camshaft 3 that rotates at half the rotational speed of the crankshaft, and extend below the camshaft 3 in parallel with the camshaft 3. The valves are individually driven to open by the action of the five rocker arms 6a to 6e pivotally supported by the rocker arm shaft 5 provided so as to be swingable and capable of relative angular displacement.

  As shown in FIG. 2, the camshaft 3 includes one high lift cam 4a having a relatively large operating angle and lift amount, and two low lift cams 4d and 4e having a relatively small operating angle and lift amount, One intermediate lift cam 4b provided with an intermediate operation angle and lift amount between the high lift cam 7a and the low lift cams 4d and 4e, and one rest cam 4c equal to the diameter of the base circle portion of each cam are integrally formed. Has been. The cams 4a to 4e correspond to the free ends of the five rocker arms 6a to 6e arranged adjacent to each other on the rocker arm shaft 5. In the present embodiment, the third rocker arm 6c to which the rest cam 4c corresponds is a slipper type cam follower, and other than that, a roller type cam follower is provided, but it goes without saying that the present invention is not limited to this configuration.

  The first rocker arm 6a to which the high lift cam 4a corresponds is always maintained in the sliding contact state with the high lift cam 4a by the elastic force of the coil spring 7 provided between the part integrated with the cylinder head 1. Has been.

  In the second rocker arm 6b to which the middle lift cam 4b corresponds, the stem end of one exhaust valve 2a, which is always spring-biased in the valve closing direction, is in contact with the most free end.

  In the third rocker arm 6c to which the rest cam 4c corresponds, the stem end of the other exhaust valve 2b that is always spring-biased in the valve closing direction is in contact with the most free end.

  As with the first rocker arm 6a, the fourth rocker arm 6d to which the first low lift cam 4d corresponds is caused by the elastic force of a coil spring (not shown) provided between the part integrated with the cylinder head 1. The sliding contact state with the first low lift cam 4d is always maintained. Similarly, the fifth rocker arm 6e corresponding to the second low lift cam 4e is always maintained in the sliding contact state with the second low lift cam 4e.

  In the first to fifth rocker arms 6a to 6e adjacent to each other, a connection switching device is provided in order to switch between a state in which they can be displaced relative to each other and a state in which they can swing integrally. This connection switching device is provided on the same axis as the center of the roller cam follower 8 so as to switch the connection / disconnection between the fourth rocker arm 6d second from the right end in FIG. 2 and the third rocker arm 6c at the center. A second connection switching device provided below the rocker arm shaft 5 to switch connection / disconnection between the first connection switching device 9a and the fifth rocker arm 6e at the right end in FIG. 2 and the fourth rocker arm 6d adjacent to the left side. 9b, the third rocker arm 6c at the center, the second rocker arm 6b adjacent to the left side thereof, and the first rocker arm 6a located at the left end are provided on the same axis as the second connection switching device 9b. The third connection switching device 9c is composed of three parts.

  The rocker arm shaft 5 is provided with one second hydraulic pressure supply passage 10b having a relatively large cross-sectional area and two first and third hydraulic pressure supply passages 10a and 10c having a relatively small cross-sectional area. .

[Connection switching device]
Hereinafter, each connection switching device will be described in detail.

  In the fourth rocker arm 6d that is second from the right in FIG. 2, a bottomed first guide hole 11a that opens toward the center third rocker arm 6c is formed. In this 1st guide hole 11a, the 1st pin 13a elastically urged | biased toward the opening side by the compression coil spring 12a with which it attached between the bottom face of the 1st guide hole 11a is slidingly fitted. The diameter of the first guide hole 11a is such that the bottom side is slidable with the first pin 13a, and the opening side is somewhat larger in diameter than the bottom side.

  The central third rocker arm 6c is concentric with the first guide hole 11a in a stationary position where the base circular portion of the first low lift cam 4d is in sliding contact with the roller-type cam follower 8d of the fourth rocker arm 6d and toward the fourth rocker arm 6d. A bottomed second guide hole 11b is formed. The diameter of the second guide hole 11b is the same as the opening side of the first guide hole 11a, and the second pin 13b is slid into the inside thereof.

  The second guide hole 11b and the second pin 13b have substantially the same axial dimension, and the second pin 13b is fully inserted into the second guide hole 11b. The end surface is set to be substantially flush with the right side surface of the third rocker arm 6c. The relationship between the axial dimensions of the first guide hole 11a and the first pin 13a is about half of the axial dimension of the second pin 13b with the first pin 13a fully inserted into the bottom of the first guide hole 11a. Is set so as to fit into the opening side of the first guide hole 11a.

  An oil passage 14a communicating with a small-diameter first hydraulic pressure supply passage 10a provided in the rocker arm shaft 5 is connected to the bottom of the first guide hole 11a. The bottom of the second guide hole 11b is connected to an oil passage 14b that communicates with a small-diameter third hydraulic supply passage 10c that is also provided in the rocker arm shaft 5.

  Thus, a first connection switching device 9a for switching connection / disconnection between the third rocker arm 6c and the fourth rocker arm 6d is configured.

  In the fifth rocker arm 6e at the right end in FIG. 2, a bottomed third guide hole 11c is formed that opens toward the fourth rocker arm 6d adjacent to the left. The third pin 13c is slidably fitted in the third guide hole 11c.

  The fourth rocker arm 6d has a third guide hole 11c at a stationary position where the base circular portions of the first and second low lift cams 4d and 4e are in sliding contact with the roller cam followers 8d and 8e of the fourth and fifth rocker arms 6d and 6e. And a bottomed fourth guide hole 11d that is open to the fifth rocker arm 6e side. A fourth pin 13d that is elastically biased toward the opening side by a compression coil spring 12b mounted between the fourth guide hole 11d and the bottom surface of the fourth guide hole 11d slides into the fourth guide hole 11d. The diameter of the fourth guide hole 11d is such that the opening side is made equal to the third guide hole 11c and the bottom side is somewhat smaller in diameter than the opening side.

  The third guide hole 11c and the third pin 13c have substantially the same axial dimension, and the end face of the third pin 13c is in a state where the third pin 13c is fully inserted into the third guide hole 11c. Is set to be substantially flush with the left side surface of the fifth rocker arm 6e. The relationship between the axial dimensions of the fourth guide hole 11d and the fourth pin 13d is about half of the axial dimension of the third pin 13c with the fourth pin 11d fully inserted into the bottom of the fourth guide hole 11d. Is set so as to fit into the opening side of the fourth guide hole 11d.

  The bottom of the third guide hole 11c is connected to an oil passage 14c that communicates with a small-diameter first hydraulic pressure supply passage 10a provided in the rocker arm shaft. A drain hole 15d that communicates with the outside of the fourth rocker arm 6d is formed at the bottom of the fourth guide hole 11d.

  Thus, a second connection switching device 9b for switching connection / disconnection between the fourth rocker arm 6d and the fifth rocker arm 6e is configured.

  In the third rocker arm 6c at the center in FIG. 2, a bottomed fifth guide hole 11e that opens to the second rocker arm 6b adjacent to the left is formed. The fifth guide hole 11e has a larger diameter than the second and third guide holes 11b and 11c described above, and the fifth pin 13e is slidably engaged therewith.

  The second rocker arm 6b has a sixth guide hole 11f that is concentric with the fifth guide hole 11e and is open at both ends at a stationary position where the base circular portion of the middle lift cam 4b is in sliding contact with the roller cam follower 8b of the second rocker arm 6b. Is formed. The diameter of the sixth guide hole 11f is the same as that of the fifth guide hole 11e on the third rocker arm 6c side, and the diameter of the first rocker arm 6a side is somewhat reduced. In the sixth guide hole 11f, a sixth pin 13f having different diameters at both ends is fitted in accordance with the sixth guide hole 11f.

  The first rocker arm 6a is concentric with the sixth guide hole 11f at a stationary position in which the base circular portions of the middle lift cams 4a and 4b are in sliding contact with the roller-type cam followers 8a and 8b of the first and second rocker arms 6a and 6b. And a bottomed seventh guide hole 11g that opens toward the second rocker arm 6b. The diameter of the seventh guide hole 11g is the same as that of the reduced diameter side of the sixth guide hole 11f, and the inside of the seventh guide hole 11g is compressed by a compression coil spring 12c mounted between the bottom surface of the seventh guide hole 11g. The seventh pin 13g that is elastically biased toward the two rocker arm 6b is slid.

  The seventh guide hole 11g and the seventh pin 13g have substantially the same axial dimension, and the end surface of the seventh pin 13g is inserted in the seventh guide hole 11g. Is set to be substantially flush with the right side surface of the first rocker arm 6a.

  The relationship between the axial dimensions of the sixth guide hole 11f and the sixth pin 13f is such that the lengths of both are equal to each other, and both end surfaces of the sixth pin 13f are fitted in the sixth guide hole 11f. Is set to be substantially flush with both side surfaces of the second rocker arm 6b. The axial dimension of the fifth pin 13e is such that when the fifth pin 13e is fully inserted into the fifth guide hole 11e, about half of the sixth pin 13f is inserted into the fifth guide hole 11e. About half of the pin 13g is set to fit in the sixth guide hole 11f.

  An oil passage 14e communicating with a large-diameter second hydraulic pressure supply passage 10b provided in the rocker arm shaft 5 is connected to the bottom of the fifth guide hole 11e. The bottom of the seventh guide hole 11g is connected to an oil passage 14g that communicates with a small-diameter third hydraulic supply passage 10c that is also provided in the rocker arm shaft 5. Further, a drain hole 15f communicating with the outside of the second rocker arm 6b is formed in a portion of the sixth guide hole 11f having a different diameter.

  Thus, a third connection switching device 9c for switching connection / disconnection of the first to third rocker arms 6a to 6c is configured.

[Operation of connection switching device]
Each of the above-described connection switching devices 9a to 9c controls each of the three hydraulic pressure supply passages 10a to 10c by opening and closing an electromagnetic valve that operates according to a signal of an electronic control circuit (not shown) according to the operating state of the engine. It act | operates by interrupting the hydraulic pressure made to act on each pin 13a-13g in the guide holes 11a-11g. Hereinafter, driving variations of the two valves 2a and 2b by the operation of the connection switching devices 9a to 9c corresponding to the difference in the action situation of the pump pressure with respect to the hydraulic pressure supply paths 14a to 14g will be described.

[Hydraulic OFF to all hydraulic supply paths]
When the supply of pump hydraulic pressure to all the first to third hydraulic pressure supply paths 10a to 10c is cut off, only the axial force of the compression coil springs 12a to 12c is applied to the first to third connection switching devices 9a to 9c, respectively. Works.

  In this state, as shown in FIG. 2, the axial force of the compression coil spring 12a acting on the first pin 13a of the first connection switching device 9a causes the second guide hole 11b bottom of the third rocker arm 6c to be Since the two pins 13b are pressed against each other, the connection between the third rocker arm 6c and the fourth rocker arm 6d is broken, and both the rocker arms 6c and 6d can swing independently of each other. Further, since the third pin 13c is pressed against the bottom of the third guide hole 11c of the fifth rocker arm 6e by the axial force of the compression coil spring 12b acting on the fourth pin 13d of the second connection switching device 9b, the fourth rocker arm The connection between 6d and the fifth rocker arm 6e is broken, and both rocker arms 6d and 6e can swing independently of each other. In the third connection switching device 9c, the fifth pin 13e is pressed against the bottom of the fifth guide hole 11e of the third rocker arm 6c by the axial force of the compression coil spring 12c acting on the seventh pin 13g. Half of 13f fits in the fifth guide hole 11e and straddles between the second rocker arm 6b and the third rocker arm 6c, and half of the seventh pin 13g fits in the sixth guide hole 11f and the first rocker arm 6a and the first rocker arm 6a. The first to third rocker arms 6a to 6c are integrally coupled to each other across the two rocker arms 6b.

  In this state, the two valves 2a and 2b connected to the second and third rocker arms 6b and 6c are simultaneously driven to open by the profile of the high lift cam 4a acting on the first rocker arm 6a. At this time, the fourth rocker arm 6d is driven by the first low lift cam 4d and the fifth rocker arm 6e is driven by the second low lift cam 4e, but the third to fifth rocker arms 6c to 6e swing independently of each other. Therefore, these movements do not affect the movements of both valves 2a and 2b.

[Hydraulic on only for the second hydraulic supply path]
When the pump hydraulic pressure to the first and third hydraulic pressure supply paths 10a and 10c is cut off and the pump hydraulic pressure is supplied only to the second hydraulic pressure supply path 10b, the first and second connection switching devices 9a and 9b are respectively connected to compression coil springs. The axial force by 12a * 12b acts, and pump hydraulic pressure acts only on the 5th pin 13e of the 3rd connection switching device 9c.

  In this state, as shown in FIG. 3, the axial force of the compression coil spring 12a acting on the first pin 13a of the first connection switching device 9a causes the second guide hole 11b of the third rocker arm 6c to be Since the two pins 13b are pressed against each other, the connection between the third rocker arm 6c and the fourth rocker arm 6d is broken, and both the rocker arms 6c and 6d can swing independently of each other. Further, since the third pin 13c is pressed against the bottom of the third guide hole 11c of the fifth rocker arm 6e by the axial force of the compression coil spring 12b acting on the fourth pin 13d of the second connection switching device 9b, the fourth rocker arm The connection between 6d and the fifth rocker arm 6e is broken, and both rocker arms 6d and 6e can swing independently of each other. In the third connection switching device 9c, the hydraulic pressure of the second hydraulic pressure supply passage 10b acts only on the large-diameter fifth pin 13e, so that it resists the axial force of the compression coil spring 12c acting on the seventh pin 13g. The fifth pin 13e pushes the seventh pin 13g into the seventh guide hole 11g of the first rocker arm 6a. As a result, the connection between the first rocker arm 6a and the second rocker arm 6b and the connection between the second rocker arm 6b and the third rocker arm 6c are broken, and the first to third rocker arms 6a to 6c swing independently of each other. It becomes possible. That is, all the rocker arms can swing independently of each other.

  In this state, the profile of the high lift cam 4a acting on the first rocker arm 6a, the profile of the first low lift cam 4d acting on the fourth rocker arm 6d, and the profile of the second low lift cam 4e acting on the fifth rocker arm 6e. Does not affect the other rocker arms, and the other valve 2b connected to the third rocker arm 6c maintains the valve-closed body because the rest cam 4c is in sliding contact with the third rocker arm 6c. One valve 2a connected to 6b is driven to open by the profile of the intermediate lift cam 4b. That is, only one valve 2a is driven to open by the profile of the middle lift cam 4b.

  For example, in an engine that uses both spark ignition and premixed compression ignition, switching from spark ignition to premixed compression ignition is quicker and more reliable because premixed compression ignition is more unstable than spark ignition. It must be possible. Accordingly, as shown in the above-described embodiment, the area of the pressure receiving surface of the fifth pin 13e that moves the third connection switching device 9c to the separation side is set larger, and the second hydraulic pressure that supplies hydraulic pressure to the fifth pin 13e. If the cross-sectional area of the supply path 10b is set larger, the separation operation of the third connection switching device 9c can be further ensured.

[Hydraulic off only for the first hydraulic supply path]
When the pump hydraulic pressure to the first hydraulic pressure supply path 10a is cut off and the pump hydraulic pressure is supplied to the second and third hydraulic pressure supply paths 10b and 10c, the pump hydraulic pressure acts on the second pin 13b in the first connection switching device 9a. The axial force of the compression coil spring 12b acts on the second connection switching device 9b, and the pump hydraulic pressure acts on both the fifth pin 13e and the seventh pin 13g on the third connection switching device 9c.

  In this state, as shown in FIG. 4, the first connection switching device 9a resists the axial force of the compression coil spring 12a acting on the first pin 13a, and the first guide hole of the fourth rocker arm 6d. The second pin 13b pushes the first pin 13a into 11a. Accordingly, half of the second pin 13b is fitted into the first guide hole 11a and straddles between the third rocker arm 6c and the fourth rocker arm 6d, and the third and fourth rocker arms 6c and 6d are integrally coupled to each other. . In the second connection switching device 9b, the fourth pin 13d pushes the third pin 13c into the third guide hole 11c of the fifth rocker arm 6e by the axial force of the compression coil spring 12b acting on the fourth pin 13d. As a result, the connection between the fourth rocker arm 6d and the fifth rocker arm 6e is broken, and the fourth rocker arm 6d and the fifth rocker arm 6e can swing independently of each other. And since the pressure receiving area of the 5th pin 13e is larger, the 3rd connection switching apparatus 9c resists the axial force of the compression coil spring 12c which acts on the 7th pin 13g in the 7th guide hole 11g of the 1st rocker arm 6a. The fifth pin 13e pushes the seventh pin 13g. As a result, the connection between the first rocker arm 6a and the second rocker arm 6b and the connection between the second rocker arm 6b and the third rocker arm 6c are broken, and the first to third rocker arms 6a to 6c swing independently of each other. It becomes possible.

  In this state, the profile of the high lift cam 4a acting on the first rocker arm 6a and the profile of the second low lift cam 4e acting on the fifth rocker arm 6e have no effect on the other rocker arms. One valve 2a connected to 6b is driven to open by the profile of the intermediate lift cam 4b, and the third and fourth rocker arms 6c and 6d are integrally connected by the first connection switching device 9a. The other valve 2b connected to 6c is driven to open by the profile of the first low lift cam 4d. That is, the two valves 2a and 2b are driven with different characteristics.

  In the state shown in FIG. 3, the roller type cam follower 8d that is cantilevered by the fourth rocker arm 6d is supported by the third and fourth rocker arms 6c and 6d in the state shown in FIG. The As described above, when the profile of the first low lift cam 4d is not transmitted to the other valve 2b, that is, when the stress acting on the roller-type cam follower 8d is small, this is used as a cantilever support, whereby the fourth rocker arm 6d. The size of the rocker shaft 5 in the axial direction can be made smaller than that of a structure in which a conventional roller cam follower is supported at both ends. In a state where the other valve 2b is lifted by the first low lift cam 4d, the roller cam follower 8d is supported at both ends by the third and fourth rocker arms 6c and 6d, thereby supporting the roller cam follower 8d. Rigidity can be ensured.

[Hydraulic on to all hydraulic supply lines]
When the pump hydraulic pressure is equally supplied to all of the first to third hydraulic pressure supply paths 10a to 10c, the hydraulic pressure of the first hydraulic pressure supply path 10a is also applied to the first pin 13a of the first connection switching device 9a with respect to the above-described state. However, since the pressure receiving area of the second pin 13b is larger, the second pin 13b is opposed to the axial force of the compression coil spring 12a acting on the first pin 13a as shown in FIG. The state in which the 1 pin 13a is pushed into the first guide hole 11a of the fourth rocker arm 6d, that is, the third and fourth rocker arms 6c and 6d are maintained integrally. The third connection switching device 9c is also maintained in the above-described state, that is, the first to third rocker arms 6a to 6c can swing independently of each other. The second connection switching device 9b is configured such that the third pin 13c and the fourth guide hole 11d of the fourth rocker arm 9d resist the axial force of the compression coil spring 12b by the hydraulic pressure acting on the third pin 13c. Push in. Accordingly, half of the third pin 13c is fitted into the fourth guide hole 11d and straddles between the fourth rocker arm 6d and the fifth rocker arm 6e, and the fourth and fifth rocker arms 6d and 6e are integrally coupled to each other. .

  In this state, the profile of the high lift cam 4a acting on the first rocker arm 6a has no effect on the other rocker arms, and one valve 2a connected to the second rocker arm 6b is driven by the profile of the middle lift cam 4b. The third to fifth rocker arms 6c to 6e are integrally connected by the first and second connection switching devices 9a and 9b, and the other valve 2b connected to the third rocker arm 6c is connected to the first, The valve is driven to open by the profile of the second low lift cams 4d and 4e. That is, the two valves 2a and 2b are driven with different characteristics. Here, the phase angles of the two low lift cams 4d and 4e are different from each other, and in particular, the timing of the second low lift cam 4e is set so as to open in the intake stroke. Thereby, high temperature exhaust from other cylinders can be introduced in the intake stroke, and the ignitability can be improved.

  In the device of the present invention described above, the hydraulic pressure from the common third hydraulic pressure supply passage 10c is supplied to the second pin 13b of the first connection switching device 9a and the seventh pin 13g of the third connection switching device 9c. The first pin 13a of the first connection switching device 9a is supplied with hydraulic pressure from the first hydraulic pressure supply passage 10a, and the fifth pin 13e of the third connection switching device 9c is supplied with hydraulic pressure from the second hydraulic pressure supply passage 10b. The The areas of the pressure receiving surfaces of the connection switching devices 9a and 9c are different from each other (second pin 13b> first pin 13a, fifth pin 13e> seventh pin 13g). Accordingly, by appropriately interrupting the hydraulic pressure to the three hydraulic pressure supply paths 10a to 10c, the first and third connection switching devices 9a and 9c can be freely driven in both directions simultaneously or one by one. . The operating procedure will be described below.

When both the connection switching devices 9a and 9c are to be connected (first 1: contact, third: contact), the pump hydraulic pressure is supplied only to the third hydraulic pressure supply passage 10c (first 1: OFF, second: OFF, 3rd: ON).
When both the connection switching devices 9a and 9c are desired to be separated (first 1: disconnected, third: disconnected), the pump hydraulic pressure is supplied to the first and second hydraulic pressure supply passages 10a and 10b (first 1: ON). Second: ON, Third: OFF).
When it is desired to separate the first connection switching device 9a and connect the third connection switching device 9c (first 1: disconnected, third: contact), pump hydraulic pressure is supplied to the first and second hydraulic pressure supply passages 10a, 10b. (First 1: ON, second: ON, third: OFF).
When the first connection switching device 9a is connected and the third connection switching device 9c is to be separated (first contact, third: disconnection), the pump hydraulic pressure is supplied to the second and third hydraulic pressure supply passages 10b and 10c. (First 1: OFF, second: ON, third: ON).

  By appropriately switching the above operating characteristics according to the operating state of the engine, for example, it is possible to improve the output characteristics over a wide operating range after using both spark ignition and premixed compression ignition. Of course, the present invention is equally applicable not only to an engine that switches between spark ignition and premixed compression ignition, but also to a valve operating device for an engine that switches operation characteristics in multiple stages.

  Note that the compression coil spring 12a of the first connection switching device 9a and the compression coil spring 12c of the third connection switching device 9c in the above-described embodiment prevent each pin from being biased when the hydraulic pressure is not applied in either direction. Since the response is not particularly required, the spring constant may be lower than that of the compression coil spring 12b of the second connection switching device 9b for returning the pin.

It is principal part side sectional drawing of the valve operating apparatus with which this invention apparatus was applied. It is a schematic block diagram of the starting / high-load area | region state of this invention apparatus by the cut surface in alignment with the II-II line in FIG. It is a schematic block diagram similar to FIG. 2 which shows the switching area | region state of the ignition mode of this invention apparatus. It is a schematic block diagram similar to FIG. FIG. 3 is a schematic configuration diagram similar to FIG. 2 showing a state of the other cylinder EGR introduction region of the device of the present invention.

Explanation of symbols

6a to 6e First to fifth rocker arms 9a to 9c First to third connection switching devices 10a to 10c First to third hydraulic pressure supply paths 13a to 13g First to seventh pins

Claims (2)

At least three transmission members arranged adjacent to each other to transmit the lift of cams having different characteristics to the valve, and connection / disconnection between the adjacent transmission members are selected on the same axis when connecting. A valve operating apparatus for an engine having a plurality of pins arranged and two connection switching devices that hydraulically move the plurality of pins to a connection position and a movement to a non-connection position,
For each of the connection switching devices, both end surfaces of the plurality of pins are connected to separate hydraulic supply passages that are controlled to be opened and closed by electromagnetic valves as pressure receiving surfaces, and the areas of both pressure receiving surfaces are different from each other ,
The hydraulic pressure supply path connected to the pressure receiving surface on the side having the larger pressure receiving area in one of the connection switching devices and the hydraulic pressure supply path connected to the pressure receiving surface on the side of the smaller pressure receiving area in the other connection switching device are characterized in common. The valve operating device of the engine. For at least one cross-sectional area of the cross-sectional area of the hydraulic pressure supply passage that connects the pressure receiving surface of the pressure receiving area is large side hydraulic pressure supply passage that connects the pressure-receiving surface of the side pressure-receiving area is small among the two connecting switching device The valve operating apparatus for an engine according to claim 1, wherein the valve operating apparatus is larger than that of the engine.

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