JP2011196334A - Hydraulic governor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To overcome problems wherein, in the existing hydraulic governor, there is a technology to suppress overshoot of a power piston connected and interlocked with a fuel injection device and to prevent hunting of the amount of fuel injected; however, it is impossible to prevent jiggling caused by a control valve controlling hydraulic fluid to the power piston, thereby causing noise and deteriorating the operating condition of an engine.SOLUTION: In this hydraulic governor, an initial gradual increase port structure 66 is provided for suppressing the hydraulic pressure fluctuation of the hydraulic fluid to the power piston 3 by providing the gradual increase region of the opening area in the initial stage of the movement of a spool 22 with respect to the variations of the opening area of a control port 18, and minute movement suppressing/connecting structures 67A, 67B are provided for suppressing the minute movement of a compensating piston 8 by interposing at least one of a looseness 72 and buffer springs 79, 80 in the connecting portion of a force transmission path leading from the power piston 3 to the compensating piston 8, with respect to the minute movement of the power piston 3 caused by the hydraulic pressure fluctuation.

Description

  The present invention relates to a hydraulic governor that controls the amount of fuel injection from a fuel injection device of an engine according to the engine speed, and more particularly to the configuration of a control port and each connecting portion that are effective for stabilizing the operating state of the engine.

  Conventionally, in a hydraulic governor that controls the fuel injection amount from a fuel injection device of an engine such as a diesel engine according to the engine speed, the overshoot of the power piston linked to the fuel injection device is suppressed, and the fuel injection A technique for preventing the amount of hunting is known (for example, see Patent Document 1).

  As shown in FIG. 8, the hydraulic governor 101 according to the technology includes a power piston 103 that is coupled and interlocked with a fuel injection device (not shown), a control valve 105 that controls hydraulic oil to the power piston 103, and the power piston 103. A compensating piston 108 that is interlockedly connected to the engine via a connecting rod 116 and a hydraulic control oil chamber 115 that is one of the oil chambers 114 and 115 that are partitioned by the power piston 103 are connected to the sleeve of the control valve 105. A control oil passage 119 communicating with a control port 118 provided on an inner peripheral surface portion 117 and a compensator oil chamber 110 of both side oil chambers 110 and 111 partitioned by the compensating piston 108 are connected to a spool of the control valve 105. Compensation communicating with one end of 122 And a road 120. The power piston 103, the control valve 105, and the compensating piston 108 are all built in the housing 102.

  The spool 122 is interlocked with the flyweight 113 and moves upward in the figure as the engine speed increases. By the movement of the spool 122, the hydraulic control oil chamber 115 on the lower side of the power piston 103 becomes The control oil passage 119 communicates with the tank 109 via the control port 118, the drain port 240, and the drain oil passage 241, and the hydraulic pressure in the hydraulic control oil chamber 115 decreases, so that the power piston 103 moves downward in the figure. As a result, the fuel injection amount decreases. On the contrary, the spool 122 moves downward in the figure when the engine speed decreases, and the movement of the spool 122 causes the high pressure oil chamber 114 above the power piston 103 and the hydraulic control oil chamber 115 to move. Since high-pressure oil is supplied, the power piston 103 moves upward in the figure due to the difference in pressure receiving area between the oil chambers 114 and 115, and the fuel injection amount increases.

  Due to the movement of the power piston 103 in the fuel decreasing direction, the volume of the compensator oil chamber 110 above the compensating piston 108 increases. Then, the hydraulic pressure (hereinafter referred to as “compensator pressure”) acting on the spool 122 via the compensation oil passage 120 communicating with the compensator oil chamber 110 becomes negative pressure and acts on the spool 122. In the figure, the movement in the lower direction, that is, the fuel increasing direction is promoted. On the contrary, when the volume of the compensator oil chamber 110 decreases due to the movement of the power piston 103 in the fuel increasing direction, the compensator pressure becomes a positive pressure and acts on the spool 122. Movement in the fuel decreasing direction is promoted. The oil chamber 111 below the compensating piston 108 communicates with a tank 109 so that a substantially constant hydraulic pressure is applied to the lower surface of the compensating piston 108.

  In this way, overshoot of the power piston 103 is suppressed, the response speed of the change in the fuel injection amount with respect to the change in the engine speed is increased, and hunting is prevented. The connecting rod 116 is inserted and fixed with respect to the compensating piston 108, while the power piston 103 is vertically moved so as not to suppress the movement of the power piston 103 more than necessary. The buffer springs 106 and 107 are interposed in a compressed state.

Japanese Utility Model Publication No. 6-43231

  However, in the above technique, although hunting can be prevented, the control valve which is essentially in a stationary state is assumed to be micro-vibration (hereinafter referred to as “jiggling”) by a slight disturbance such as a change in high-frequency micro-rotation speed on the engine output shaft. ) Is not supported. That is, due to this jiggling, the power piston that is directly controlled by the control valve also causes significant fibrillation, and the compensating piston that is linked to this power piston also fibrillates, causing the compensator pressure to fluctuate. As a result, the minute vibration of the spool in the control valve is promoted, and the jiggling continues. As a result, the link portion connecting the power piston to the fuel injection device (not shown) vibrates, and abnormal noise is generated, or fine friction occurs between the members of the link portion, and the operating state of the engine deteriorates. There was a problem.

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.
That is, according to the first aspect of the present invention, the power piston interlocked with the fuel injection device of the engine, and the control valve for switching the oil passage of the hydraulic oil to the power piston as the spool land moves in the sleeve having the control port opened. And a compensating piston that is linked to the power piston via a connecting rod, and controls the supply and discharge of hydraulic oil from the control port by applying hydraulic pressure to the spool by the movement of the compensating piston. In the hydraulic governor that suppresses overshoot of the power piston, a gradually increasing region in which the change rate of the opening area with respect to the amount of movement of the spool is small with respect to the fluctuation of the opening area of the control port due to the minute vibration of the control valve. By providing it at the beginning of movement, In which the provided initial incremental port structure suppresses the pressure variation of aggressive media.
According to a second aspect of the present invention, a plurality of substantially identical control ports are opened in the inner peripheral surface portion of the sleeve, and the opening edge portion of at least one control port of the control port is spooled more than the opening edge portion of the other control port. It is arranged by shifting a predetermined distance in the moving direction.
According to a third aspect of the present invention, the plurality of control ports are continuously shifted in any one of the spool movement directions.
According to a fourth aspect of the present invention, the predetermined distance is set to 40 μm or more.
According to a fifth aspect of the present invention, a plurality of large-diameter main control ports and sub-control ports smaller than the main control port are opened on the inner peripheral surface portion of the sleeve, and an opening edge of the sub-control port is formed on the main control port It is arranged so as to protrude a predetermined distance in the spool movement direction from the opening edge.
The area ratio of the sub control port to the main control port is set to 10% or less.
According to a seventh aspect of the present invention, the control port is formed in a substantially circular shape in cross section.
According to claim 8, at least one control port having a non-circular cross-sectional view is opened in the inner peripheral surface portion of the sleeve, and an opening edge portion of the control port includes a large opening edge portion having a large opening area and an opening portion. The small opening edge is formed by projecting a predetermined distance from the large opening edge in the spool moving direction.
In claim 9, a power piston interlocked with the fuel injection device of the engine, a control valve for switching the oil passage of the hydraulic oil to the power piston by moving the land of the spool in the sleeve having the control port opened, A compensating piston that is linked to the power piston via a connecting rod, and by moving the compensating piston, hydraulic pressure is applied to the spool to control the supply and discharge of hydraulic oil from the control port; In the hydraulic governor for suppressing overshoot of the power piston, a connecting portion of a transmission path of a force from the power piston to the compensating piston with respect to fine movement of the power piston due to hydraulic pressure fluctuation of hydraulic oil from the control valve And at least one of play and elastic body By, it is provided with a fibrillation suppressing fibrillation suppression connection structure of the Compensating piston.
According to a tenth aspect of the present invention, the connecting rod is slidably inserted into the rod hole in the power piston, and a pair of elastic bodies each having one end fixed in the rod hole are provided in the rod hole. With the elastic body, the first clamping member and the second clamping member are arranged so as to be movable only in the separating direction while being urged in the approaching direction, and the first clamping member and the second clamping member A support portion of the connecting rod is interposed between the support portion and the first holding member, or at least one of the support portion and the second holding portion.
In the eleventh aspect, the connecting rod is slidably inserted into the compensating piston, and the front and rear side surfaces in the moving direction of the compensating piston are attached by the pair of elastic bodies whose one ends are fixed to the connecting rod. It is sandwiched in a state where it is in force.

Since this invention was comprised as mentioned above, there exists an effect shown below.
That is, according to the first aspect, the displacement width of the spool can be accommodated in the gradually increasing region, and a sudden change in the opening area can be reduced, and the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the control port to the power piston can be greatly increased. The power piston fibrillation itself can be reduced. As a result, the fibrillation that occurs in the compensating piston is also reduced to improve jiggling resistance, the vibration of the link portion linked to the power piston is prevented, noise is suppressed, and the engine operating state is stabilized. be able to.
According to the second aspect, compared with the case where the size and shape of each control port is changed, the opening process of the control port can be easily performed, and the processing cost can be reduced and the processing time can be shortened.
According to the third aspect, the positioning of the plurality of control ports is facilitated, and the processing cost and the processing time can be further reduced. In addition, the gradual increase area can be enlarged by passing the spool lands sequentially through the opening edge of the control port, and even if the displacement width of the spool is large, the initial change of the opening area It is possible to reliably reduce the speed, greatly reduce the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston, and reduce the power piston fibrillation itself.
According to the fourth aspect of the present invention, it is possible to provide a gradually increasing region in a sufficient range, and even when the displacement width of the spool is large, the initial change speed of the opening area is reliably reduced, and the power piston is supplied and discharged. Fluctuations in hydraulic oil pressure can be greatly reduced, and the power piston fibrillation itself can be reduced.
According to claim 5, by changing the size, shape, position, etc. of the sub control port, the range of the gradually increasing region and the changing speed of the opening area in the gradually increasing region are optimized according to the form of the minute vibration. It is possible to reliably reduce the initial change speed of the opening area, greatly reduce the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston, and reduce the power piston fibrillation itself.
According to the sixth aspect of the present invention, it is possible to provide a gradually increasing region in a sufficient range, and even when the displacement width of the spool is large, the initial change speed of the opening area is reliably reduced, and the power piston is supplied and discharged. Fluctuations in hydraulic oil pressure can be greatly reduced, and the power piston fibrillation itself can be reduced.
According to the seventh aspect, it is possible to easily perform the opening processing of the control port, and it is possible to reduce the processing cost and the processing time.
According to claim 8, the land of the spool passes through the small opening edge to the large opening edge in order, so that a gradual increase area can be provided even with a single control port, and the numerical aperture of the control port is reduced. It is possible to reduce the processing cost and the processing time.
According to the ninth aspect, the displacement width of the fibrillation can be reduced by the width of the play or by the amount via the elastic body, and the fibrillation transmitted to the compensating piston can be reduced. As a result, the fibrillation that occurs in the compensating piston is also reduced to improve jiggling resistance, the vibration of the link portion linked to the power piston is prevented, noise is suppressed, and the engine operating state is stabilized. be able to.
According to the tenth aspect, even when the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston is large and the power piston is finely moved, the displacement width of the power piston is reliably reduced and transmitted by the width of the play. It is possible to block most of the fibrillation transmitted from the power piston to the connecting rod, and sufficiently reduce the fibrillation occurring in the compensating piston.
According to the eleventh aspect, fibrillation from the connecting rod can be suppressed by the elastic body between the connecting rod and the compensating piston, and the fibrillation occurring in the compensating piston can be sufficiently reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial side sectional view showing an overall configuration of a hydraulic governor according to the present invention. It is side surface partial sectional drawing of a control valve. It is AA arrow sectional drawing of FIG. It is an expanded view of the internal peripheral surface part of a sleeve which shows an initial stage increase port structure. It is an expanded view of the internal peripheral surface part of a sleeve which shows another form of the initial gradually increasing port structure which has a sub control port. It is an expanded view of the internal peripheral surface part of a sleeve which shows another form of the initial increase port structure which has a noncircular control port. It is side surface partial sectional drawing of a power piston and a compensating piston which shows a fibrillation suppression connection structure. It is side surface partial sectional drawing which shows the whole structure of the conventional hydraulic governor.

Hereinafter, embodiments of the present invention will be described in detail.
The direction indicated by the arrow L and the direction indicated by the arrow U in FIG. 1 are the left direction and the upward direction of the hydraulic governor 1, respectively, and the position and direction of each member described below will be described.

First, the overall configuration of the hydraulic governor 1 according to the present invention will be described with reference to FIG.
The hydraulic governor 1 includes a housing 2 in which a power piston 3 is built. The power piston 3 is connected via a link mechanism 68 to an output lever 69 that is swingably mounted around the housing 2 and the output shaft 70, and the output lever 69 is connected to a fuel injection (not shown). It is linked to the control rack of the device.

  A pair of oil chambers 14 and 15 are partitioned by the power piston 3, and the oil chambers 14 and 15 are both formed in the housing 2, and the pressure receiving area of the power piston 3 has a high pressure on the upper side. The pressure receiving area in the oil chamber 14 is set to be smaller than the pressure receiving area in the lower hydraulic control oil chamber 15.

  The housing 2 contains a hydraulic pump 4. The hydraulic pump 4 is a gear pump having a drive gear 32 and a driven gear 33 that mesh with each other, and power is transmitted to the drive gear 32 from a crankshaft (not shown). It is integrated with a sleeve 17 that is rotatably inserted into the housing 2.

  A flyweight 13 is rotatably attached to the upper end of the sleeve 17. A spool 22 is connected to one end of the flyweight 13, and the control valve 5 is constituted by the spool 22 and the sleeve 17.

  As a result, when the engine (not shown) is operated and the drive gear 32 is rotated, the sleeve 17 is rotated and the flyweight 13 is displaced by centrifugal force, the spool 22 moves in the vertical direction according to the displacement amount. To do. Then, when the rotation of the sleeve 17 exceeds the set rotation, the control valve 5 is switched, and hydraulic oil is supplied to and discharged from the hydraulic pump 4 to the power piston 3.

  The housing 2 contains a compensating piston 8. The compensating piston 8 and the power piston 3 are connected to a connecting rod 16 via a fibrillation suppressing connecting structure, which will be described later.

  A pair of oil chambers 10 and 11 are partitioned by the compensating piston 8, and the oil chambers 10 and 11 are both formed in the housing 2 and communicated with the tank 9. Among these, a needle valve 12 as a compensator valve is interposed between the upper compensator oil chamber 10 and the tank 9.

  The needle valve 12 and the compensator oil chamber 10 communicate with the insertion hole 34 of the sleeve 17 of the control valve 5, and the oil pressure of the compensator oil chamber 10 is spooled 22 through the compensation oil passage 20. It acts on the lower end side of.

  In such a configuration, when the engine speed increases, the flyweight 13 opens and the spool 22 of the control valve 5 moves upward, and the annular land 21 provided integrally with the spool 22 is also attached to the sleeve 17. While moving in sliding contact with the inner peripheral surface portion 17a, the opening area on the opening side of the control port 18 having an initial gradually increasing port structure to be described later is changed. Then, a control oil passage 19 communicating with the hydraulic control oil chamber 15 on the lower side of the power piston 3 is connected to the tank 9 which is a low pressure portion via the control port 18, while Only the high-pressure oil chamber 14 on the side is supplied with high-pressure oil from the hydraulic pump 4 via a high-pressure oil passage 23. Due to this hydraulic pressure difference, the power piston 3 moves downward, the fuel injection amount decreases, and the engine speed decreases.

  Conversely, when the engine speed is reduced, the flyweight 13 is closed, the spool 22 of the control valve 5 is moved downward, and the land 21 is also moved downward while being in sliding contact with the inner peripheral surface portion 17a of the sleeve 17, The opening area on the opening side of the control port 18 is changed. Then, the hydraulic pump 4 is connected to the control oil passage 19 communicating with the hydraulic control oil chamber 15 on the lower side of the power piston 3 via the control port 18. High pressure oil is supplied to both of the oil chambers 14 and 15. Here, as described above, since the pressure receiving area is smaller in the high pressure oil chamber 14 on the upper side, the power piston 3 moves upward, the fuel injection amount increases, and the engine speed increases.

  Further, in conjunction with the fuel decreasing direction of the power piston 3, that is, downward movement, the compensating piston 8 coupled via a fibrillation suppression coupling structure described later also moves downward. Then, the vertical height of the compensator oil chamber 10 which is an upper oil chamber partitioned by the compensating piston 8 is also increased, the volume is increased, the compensator pressure becomes negative pressure, and the spool 22 The upward movement, that is, the further movement in the fuel decreasing direction is suppressed. Conversely, the compensating piston 8 moves upward in conjunction with the fuel increasing direction of the power piston 3, that is, the upward movement. Then, the vertical height of the compensator oil chamber 10 is reduced, the volume is reduced, the compensator pressure becomes positive, and the spool 22 moves downward, that is, moves further in the fuel increasing direction. It is suppressed.

  In this way, since the overshoot of the power piston 3 controlled by the control valve 5 is suppressed, the response speed of the change in the fuel injection amount with respect to the change in the engine speed is increased, and hunting is prevented. It should be noted that the adjustment of the compensator pressure at this time is performed by adjusting the opening of the needle valve 12, whereby the settling time of the engine speed can be adjusted.

  A control lever 25 for setting the engine speed is swingably attached to the housing 2, and a compression spring 27 is connected to the control lever 25 via a link mechanism 26. 27, an elastic force is applied to press the spool 22 of the control valve 5 downward, that is, in the fuel increasing direction. Since the elastic force is changed by the operation of the control lever 25, the engine speed can be changed by moving the spool 22 by operating the control lever 25.

Next, the control port 18 will be described with reference to FIGS.
First, the oil passage switching structure in the control valve 5 will be described in detail.
As shown in FIGS. 1 to 3, in the control valve 5, upper and lower annular grooves 35, 36 communicating with the sleeve 17 with the high pressure oil passage 23 and the control oil passage 19, respectively, and the annular grooves 35, 36. A plurality of high-pressure ports 37 and control ports 18 extending in the radial direction from the respective bottom portions to the inner peripheral surface portion 17a of the sleeve 17 are formed. Of these, the high pressure port 37 communicates with the high pressure oil passage 23 via the annular groove 35, and the control port 18 is positioned below the high pressure port 37, and the control oil passage 19 via the annular groove 36. It is communicated to.

  Further, below the control port 18, the sleeve 17 includes an annular groove 39 that opens to the outer periphery thereof, and a drain port that extends in a radial direction from the bottom of the annular groove 39 to the inner peripheral surface portion 17 a of the sleeve 17. 40 is formed. The annular groove 39 communicates with the tank 9 which is a low-pressure part via a drain oil passage 41 formed in the housing 2.

  On the outer periphery of the spool 22, the land 21 having a large diameter is provided at substantially the same height as the control port 18, and an annular space is formed between the sleeve 17 and the spool 22 above the land 21. A high-pressure passage 42 having a cross section is formed, and a low-pressure passage 43 having an annular cross section is formed in a gap between the sleeve 17 and the spool 22 below the land 21. The high pressure passage 42 is communicated with the hydraulic pump 4 via a pump oil passage 44, while the low pressure oil passage 43 is communicated with the tank 9 via the drain oil passage 41.

  Furthermore, since the land 21 is in sliding contact with the inner peripheral surface portion 17a of the sleeve 17 as described above, the control port 18 is substantially closed by the outer peripheral surface portion 21a of the land 21 in the neutral state shown in FIG. ing.

  In such a configuration, when the spool 22 moves upward from the neutral state, the land 21 opens the control port 18 to the low pressure passage 43 side, and the control oil passage 19 communicates with the low pressure passage 43. As a result, the hydraulic pressure in the hydraulic control oil chamber 15 escapes from the control oil passage 19 to the tank 9 via the control port 18, the low pressure passage 43, the drain port 40, and the drain oil passage 41. Then, as described above, the power piston 3 moves downward, the fuel injection amount decreases, and the engine speed decreases.

  Conversely, when the spool 22 moves downward from the neutral state, the land 21 opens the control port 18 to the high pressure passage 42 side, and the control oil passage 19 communicates with the high pressure passage 42. Thereby, the high pressure oil from the hydraulic pump 4 is supplied from the pump oil passage 44 to the hydraulic control oil chamber 15 through the high pressure port 37, the high pressure passage 42, the control port 18, and the control oil passage 19. Then, as described above, the power piston 3 moves upward, the fuel injection amount increases, and the engine speed increases.

  As shown in FIGS. 3 and 4, in the oil path switching structure as described above, four control ports 18 having substantially the same circular shape in cross section are provided. The four control ports 18 are arranged in the circumferential direction of the inner peripheral surface portion 17a of the sleeve 17 with substantially the same central angle 90 degrees.

  Further, in the adjacent left and right control ports 18 and 18, the opening edge 47 of the right control port 18 is in one direction of the spool movement direction 46 in the present embodiment, rather than the opening edge 47 of the left control port 18. It is arranged so as to be shifted downward by a predetermined distance 45.

  In such a port structure, the opening area of the control port 18 increases with the amount of movement of the land 21, that is, the amount of movement of the spool 22. The vicinity of either the edge 47a or the lower edge 47b is continuously opened. For example, when the land 21 is moved downward, the land 21 passes through each opening edge 47 of the four control ports 18 one by one in order from the left, and the vicinity of each upper edge 47a is sequentially opened. . Thereby, the change speed of the opening area in the entire four control ports 18 can be set to be small within at least a part of the initial range of movement of the spool 22.

  On the other hand, when the four control ports 18 are arranged at the same height in the circumferential direction as in the prior art, when the spool 22 moves, the lands 21 become the opening edge portions 47 of the four control ports 18. Are simultaneously opened, and the vicinity of either the upper edge 47a or the lower edge 47b is simultaneously opened at four locations. For this reason, the change speed of the opening area in the entire four control ports 18 is large even in the initial stage of movement of the spool 22.

  That is, by the initial gradually increasing port structure 66 having the above-described configuration, a range in which the change rate of the opening area with respect to the moving amount of the spool 22 is small (hereinafter referred to as “gradually increasing region”) is provided at the initial stage of moving the spool 22. be able to.

Therefore, in a constant speed operation state, that is, in a state where the spool 22 is substantially stationary and the hydraulic pressure in the hydraulic control oil chamber 15 is kept constant, even if the spool 22 fluctuates, While the displacement width of the spool 22 is within the range, the land 21 vibrates to such an extent that the vicinity of the upper and lower edges 47a and 47b of the control port 18 is opened, and until most of the control port 18 is opened. It does n’t come. Thereby, the fluctuation | variation of the hydraulic pressure of the hydraulic fluid supplied / discharged from the control port 18 to the hydraulic control oil chamber 15 of the power piston 3 is suppressed.

  Then, in the non-constant speed operation state, in the initial stage of the movement process, only the vicinity of the upper edge 47a or the lower edge 47b is opened as described above. Since the central portion also starts to open, after the spool 22 has moved very slightly, most of the control port 18 opens, and the change rate of the opening area in the four control ports 18 as a whole increases. As a result, the hydraulic pressure of the hydraulic oil supplied to and discharged from the hydraulic control oil chamber 15 of the power piston 3 changes relatively rapidly, and the power piston 3 also moves quickly to perform a highly responsive fuel injection amount control operation. It can be carried out.

  In order to provide the gradual increase region, a configuration in which control ports having different sizes and shapes are arranged and the opening edge portion is shifted in the spool moving direction 46 is also conceivable, but from the viewpoint of workability such as opening processing, etc. As described above, a port structure in which substantially the same control port 18 is arranged with a predetermined distance 45 shifted in the spool movement direction 46 is preferable.

  Further, the control port 18 is arranged so as to be continuously shifted in one direction of the spool moving direction 46, but unlike the case where the control port 18 is arbitrarily shifted in both directions of the spool moving direction 46, Positioning becomes easy, and processing costs can be reduced and processing time can be shortened.

  The predetermined distance 45 is preferably 40 μm or more. If it is less than 40 μm, the next control port 18 is immediately opened, so that the gradually increasing area becomes narrow, and it becomes difficult to cope with jiggling having a large displacement width.

  That is, the power piston 3 interlockingly connected to a fuel injection device of an engine (not shown), and the land 21 of the spool 22 moves in the sleeve 17 having the control port 18 opened, so that the hydraulic oil passage to the power piston 3 is provided. A control valve 5 for switching, and a compensating piston 8 coupled to the power piston 3 via a connecting rod 16, and a hydraulic pressure is applied to the spool 22 by the movement of the compensating piston 8 to control the control port. In the hydraulic governor 1 that controls the supply and discharge of hydraulic oil from the 18 and suppresses the overshoot of the power piston 3, the fluctuation of the opening area of the control port 18 due to the minute vibration of the control valve 5 A gradually increasing area where the change speed of the opening area with respect to the movement amount is small Since the initial gradually increasing port structure 66 that suppresses the hydraulic pressure fluctuation of the hydraulic oil to the power piston 3 is provided by providing it at the initial stage of movement, the displacement width of the spool 22 is accommodated in the gradually increasing region, and a sudden change in the opening area is caused. It is possible to reduce the oil pressure fluctuation of the hydraulic oil supplied to and discharged from the control port 18 to the power piston 3, and to reduce the fibrillation of the power piston 3 itself. As a result, the fibrillation occurring in the compensating piston 8 is reduced to improve the jiggling resistance, and the vibration of the link portion composed of the link mechanism 68, the output shaft 70, etc. interlocked with the power piston 3 is prevented. Can be suppressed and the engine operating state can be stabilized.

  Further, a plurality of substantially identical control ports 18 are opened in the inner peripheral surface portion 17 a of the sleeve 17, and an opening edge portion 47 of at least one control port 18 of the control port 18 is an opening edge portion 47 of another control port 18. Rather than shifting the size and shape of each control port, the control port 18 can be opened more easily and the machining cost can be reduced. Processing time can be shortened.

  In particular, since the plurality of control ports 18 are continuously shifted in any one of the spool movement directions 46, positioning of the plurality of control ports 18 is facilitated, further reducing processing costs and processing time. Can be shortened. In addition, the gradual increase area can be expanded by sequentially passing the land 21 of the spool 22 through the opening edge 47 of the control port 18, and even if the displacement width of the spool 22 is large, the opening It is possible to reliably reduce the initial change speed of the area, greatly reduce the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston 3, and reduce the fibrillation of the power piston 3 itself.

  In addition, since the predetermined distance 45 is set to 40 μm or more, a sufficient gradually increasing area can be provided, and even if the displacement width of the spool 22 is large, the initial change speed of the opening area can be ensured. Thus, the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston 3 can be greatly reduced, and the fibrillation itself of the power piston 3 can be reduced.

Next, another embodiment of the initial gradually increasing port structure 66 will be described with reference to FIGS.
The initial gradually increasing port structure 66A shown in FIG. 5 is provided with upper and lower sub-control ports 29 and 30 with extremely small areas in order to reduce the change speed of the opening area in the initial stage of movement of the spool 22, and the sub-control ports 29 and 30 The opening in the initial stage of movement of the spool 22 is started.

  In the initial gradually increasing port structure 66A, four main control ports 28 having a substantially circular cross-sectional view are formed on the inner peripheral surface portion 17a of the sleeve 17 with the same height in the circumferential direction and substantially the same central angle of 90 degrees. Are arranged.

  A pair of sub-control ports 29 and 30 are arranged in a line in the vertical direction at the center of the left and right main control ports 28 adjacent to each other. The sub control ports 29 and 30 are arranged on upper and lower tangent lines 50 and 51 passing through substantially upper and lower ends of the opening edges 52 of the four main control ports 28, and the opening edges of the sub control ports 29 and 30. The portions 53 and 54 are arranged so as to protrude from the opening edge portion 52 of the main control port 28 by a predetermined distance 48a and 48b in the spool moving direction 46, in this embodiment, in the vertical direction, respectively.

  In such a configuration, for example, when the land 21 is moved downward, the land 21 passes through the opening edge 53 of the upper sub-control port 29, and the upper sub-control port 29 having a small area gradually starts from the top. It will be opened. Thereby, the change speed of the opening area in the initial stage of movement of the spool 22 can be set small. Accordingly, in the constant speed operation state, even if the spool 22 fluctuates, the land 21 vibrates to such an extent that the upper sub control port 29 is opened. Therefore, until the main control port 28 having a large area is opened. Accordingly, fluctuations in the hydraulic pressure of the hydraulic oil supplied and discharged from the control ports 28, 29, and 30 to the hydraulic control oil chamber 15 of the power piston 3 are suppressed.

  Further, when the land 21 is moved downward and exceeds the predetermined distance 48a, the land 21 passes through the opening edge 52 of the main control port 28, and the large-area main control port 28 also starts to open. Accordingly, in the non-constant speed operation state, at the initial stage of movement, in the same manner as described above, after the upper sub-control port 29 is opened, the large-diameter main control port 28 is subsequently opened. 28, the change speed of the opening area is increased, the hydraulic pressure of the hydraulic oil supplied to and discharged from the hydraulic control oil chamber 15 of the power piston 3 changes relatively rapidly, and the control operation of the highly responsive fuel injection amount is performed. Can do.

  Note that by changing the size, shape, position, etc. of the sub-control ports 29, 30, the range of the gradually increasing area can be expanded and the rate of change of the opening area in the gradually increasing area can be increased or decreased. For example, when the displacement width of the spool 22 is large, the range of the gradually increasing area can be expanded by making the sub control ports 29 and 30 oval vertically long and elongating the protruding portion.

  The area ratio S2 / S1 of the opening areas S2 of the upper and lower sub-control ports 29 and 30 with respect to the opening area S1 of the main control port 28 is preferably 10% or less. If it exceeds 10%, the sub control ports 29 and 30 are too large, and the change speed of the opening area in the gradually increasing region becomes large, and the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the hydraulic control oil chamber 15 of the power piston 3 becomes severe. Because.

  That is, a large-diameter main control port 28 and a plurality of sub-control ports 29 and 30 smaller than the main control port 28 are opened in the inner peripheral surface portion 17a of the sleeve 17, and an opening edge portion 53 of the sub-control ports 29 and 30 is opened. 54 is arranged so as to protrude from the opening edge 52 of the main control port 28 by a predetermined distance 48a and 48b in the spool moving direction 46, respectively, so that the size, shape, position, etc. of the sub control ports 29 and 30 are determined. By changing, it is possible to optimize the range of the gradually increasing area and the change speed of the opening area in the gradually increasing area according to the form of jiggling that is minute vibration, and reliably reduce the initial changing speed of the opening area. Thus, the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston 3 can be greatly reduced, and the fibrillation itself of the power piston 3 can be reduced.

  Furthermore, since the area ratio S2 / S1 of the sub-control ports 29 and 30 with respect to the main control port 28 is set to 10% or less, a sufficiently increasing range can be provided and the displacement width of the spool 22 is large. Even so, it is possible to reliably reduce the initial change speed of the opening area, greatly reduce the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston 3, and reduce the fibrillation of the power piston 3 itself. it can.

  The control ports 18, 28, 29, and 30 of the initial gradually increasing port structure 66 and 66A described above are all formed in a substantially circular shape in sectional view, which is preferable from the viewpoint of workability such as opening processing. That is, since the control ports 18, 28, 29, and 30 are formed in a substantially circular shape when viewed in cross section, the opening of the control ports 18, 28, 29, and 30 can be easily performed, thereby reducing processing costs and processing. Time can be shortened.

  Further, the initial gradually increasing port structure 66B shown in FIG. 6 is provided with openings 55b and 55c having extremely small areas in the single control port 55 in order to reduce the change speed of the opening area in the initial stage of movement of the spool 22. The opening at the initial stage of movement of the spool 22 is started from the openings 55b and 55c.

  In the initial gradually increasing port structure 66B, a control port 55 having a non-circular sectional view is formed on the inner peripheral surface portion 17a of the sleeve 17. The opening edge 56 of the control port 55 includes a large opening edge 56a of the substantially circular and large area opening 55a and a small opening edge 56b and 56c of the substantially semicircular and small area opening 55b and 55c. The small opening edge portions 56b and 56c are projected from the large opening edge portion 56a by a predetermined distance 57a and 57b in the spool moving direction 46, in this embodiment, in the vertical direction, respectively.

  In such a configuration, for example, when the land 21 is moved downward, the land 21 passes through the small opening edge 56b, and the small-area opening 55b is gradually opened. Thereby, the change speed of the opening area in the initial stage of movement of the spool 22 can be set small. Accordingly, even when the spool 22 fluctuates in the constant speed operation state, the land 21 vibrates to such an extent that the small-area opening 55b is opened, so that the large-area opening 55a is not opened. Thus, fluctuations in the hydraulic pressure of the hydraulic oil supplied to and discharged from the hydraulic control oil chamber 15 of the power piston 3 are suppressed.

  Further, when the land 21 is moved downward and exceeds the predetermined distance 57a, the land 21 also passes through the large opening edge 56a, and the large-area opening 55a starts to open. Therefore, in the non-constant speed operation state, in the initial stage of the movement, in the same manner as described above, after the vicinity of the small opening edges 56a and 56b is opened, the change speed of the opening area in the entire single control port 55 The hydraulic pressure of the hydraulic oil supplied to and discharged from the hydraulic control oil chamber 15 of the power piston 3 changes relatively rapidly, and a highly responsive fuel injection amount control operation can be performed.

  Since such a control port 55 is formed in a non-circular shape in a cross-sectional view, the gradual increase region is provided only by the single control port 55 by optimizing its size, shape, position, etc. be able to.

  That is, at least one control port 55 having a non-circular sectional view is opened in the inner peripheral surface portion 17a of the sleeve 17, and the opening edge portion 56 of the control port 55 is a large opening edge portion 56a of the opening portion 55a having a large opening area. And small opening edges 56b and 56c of the openings 55b and 55c having a small opening area. The small opening edges 56b and 56c are respectively separated by a predetermined distance 57a from the large opening edge 56a in the spool moving direction 46. -Since it is formed by projecting 57b, the land 21 of the spool 22 passes through the small opening edge portions 56b and 56c in this order from the large opening edge portion 56a so that a single control port 55 can be provided with a gradually increasing area. Thus, the numerical aperture of the control port 55 can be reduced to reduce the processing cost and the processing time.

Next, a connection structure among the power piston 3, the connecting rod 16, and the compensating piston 8 will be described with reference to FIG.
First, a connection structure between the power piston 3 and the connection rod 16 will be described.
A rod hole 58 for penetrating the connecting rod 16 from below is provided in a substantially central portion in plan view of the power piston 3, and an upper spring chamber 58a and an upper spring are disposed in the rod hole 58 in order from the top. A support hole 58b having a smaller inner diameter than the chamber 58a, a swing chamber 58c having substantially the same inner diameter as the upper spring chamber 58a, and a lower spring chamber 58d having a larger inner diameter than the swing chamber 58c are formed. Yes.

  Among these, in the upper spring chamber 58a, a fixing ring 59 is fitted on the inner wall of the power piston 3 at the upper portion of the upper spring chamber 58a, and between the support hole 58b at the bottom of the upper spring chamber 58a. A movable disk 60 is placed on the shoulder 3a formed in the upper part, and an upper buffer spring 6 is interposed between the movable disk 60 and the fixed ring 59 in a compressed state.

  In the lower spring chamber 58d, a fixing ring 62 is fitted on the inner wall of the power piston 3 at the lower portion of the lower spring chamber 58d, and is formed between the rocking chamber 58c at the top of the lower spring chamber 58d. The upper surface of the movable ring 61 is in contact with the shoulder portion 3c, and the lower buffer spring 7 is interposed between the movable ring 61 and the fixed ring 62 in a compressed state.

  The connecting rod 16 penetrating from below into the lower spring chamber 58d passes through the support hole 58b from the swing chamber 58c, and then comes into contact with the lower surface of the movable disk 60. Further, a flange 16 a is formed on the outer periphery of the connecting rod 16, and a play 72 having a predetermined width 71 is provided between the lower surface of the flange 16 a and the upper surface of the movable ring 61.

  That is, a portion (hereinafter referred to as “support portion”) 73 including the flange 16 a and the rod upper portion 16 b above the flange 16 a is sandwiched between the movable disk 60 and the movable ring 61. In addition, the length 74 of the support portion 73 is set to be shorter than the distance 75 between the movable disk 60 and the movable ring 61 by the play 72.

  In such a configuration, when the power piston 3 moves upward, the movable ring 61 pushes up the lower surface of the flange 16a via the lower buffer spring 7 to move the connecting rod 16 upward. When it moves downward, the movable disk 60 pushes down the upper end of the rod upper portion 16b via the upper buffer spring 6 and moves the connecting rod 16 downward. In this way, the connecting rod 16 moves with the movement of the power piston 3.

  When the connecting rod 16 is stationary at a predetermined position and the oil pressure in the oil pressure control oil chamber 15 is kept constant, the power 72 is powered in the play 72 even if the power piston 3 is fibrillated. The displacement width of the piston 3 is adjusted. As a result, only the power piston 3 is finely moved, and the support portion 73 is not pushed by the movable disk 60 or the movable ring 61, and until the compensating piston 8 is finely moved via the connecting rod 16. It does n’t come.

  That is, the fine movement of the power piston 3 is blocked by the fine movement suppressing connection structure 67 </ b> A having the above-described configuration, and the connection rod 16 is not finely moved. The play 72 may be provided between the lower surface of the movable disk 60 and the front end surface of the support portion 73. If the play 72 exceeds the displacement width of the power piston 3 as a whole, its size and position are There is no particular limitation.

  That is, the connecting rod 16 is slidably inserted into the rod hole 58 in the power piston 3, and the rod hole 58 has a pair of elastic bodies with one end fixed in the rod hole 58. The buffer springs 6 and 7 are provided, and the buffer springs 6 and 7 separate the movable disc 60 that is the first clamping member and the movable ring 61 that is the second clamping member in a state in which they are biased toward each other. And a support portion 73 of the connecting rod 16 is interposed between the movable disk 60 and the movable ring 61, and between the support portion 73 and the movable disk 60 or the support. Since the play 72 is provided in at least one of the portion 73 and the movable ring 61, even when the hydraulic pressure fluctuation of the hydraulic oil supplied to and discharged from the power piston 3 is large and the power piston 3 is finely moved, The displacement width of the power piston 3 can be reliably reduced and transmitted by the width of the play 72, most of the fibrillation transmitted from the power piston 3 to the connecting rod 16 is cut off, and the compensating piston 8 The fibrillation that occurs in can be reduced sufficiently.

A connection structure between the connecting rod 16 and the compensating piston 8 will be described.
A rod hole 76 for penetrating the connecting rod 16 from above is provided at a substantially central portion in plan view of the compensating piston 8, and a lower portion of the connecting rod 16 is slidably inserted into the rod hole 76. Has been.

  Fixing rings 77 and 78 are fitted on and fixed to the outer periphery of the connecting rod 16 up and down on the connecting rod 16 with the compensating piston 8 interposed therebetween, and the upper fixing ring 77 and the compensating piston of these are fixed. 8, an upper buffer spring 79 is interposed in a compressed state, and a lower buffer spring 80 is interposed between the compensating piston 8 and the lower fixing ring 78 in a compressed state.

  In such a configuration, when the connecting rod 16 moves upward with the power piston 3, the compensating piston 8 is moved upward via the lower buffer spring 80, and conversely, the connecting rod 16 moves with the power piston 3. When 16 moves downward, the compensating piston 8 is moved downward via the upper buffer spring 79.

  Even when the connecting rod 16 is stationary at a predetermined position and the hydraulic pressure in the hydraulic control oil chamber 15 is maintained constant, the power piston 3 may be fibrillated and transmitted to the connecting rod 16. Since the fibrillation is transmitted to the compensating piston 8 via the upper and lower buffer springs 79 and 80, the fibrillation of the compensating piston 8 is suppressed.

  That is, fibrillation from the connecting rod 16 is suppressed by the fibrillation suppression connecting structure 67B configured as described above, and the compensating piston 8 is not fibrillated. When only play is provided between the connecting rod 16 and the compensating piston 8, the connecting rod 16 that vibrates and the compensating piston that tries to follow the connecting rod 16 with the play being delayed. Since a phase difference is generated between the first and second members and a collision occurs and there is a possibility of damage to parts, it is preferable to provide at least buffer springs 79 and 80 as in this embodiment.

  That is, the connecting rod 16 is slidably inserted into the compensating piston 8, and the front and rear side surfaces in the moving direction of the compensating piston 8 are a pair of elastic bodies with one end fixed to the connecting rod 16. Are held in a biased state by the buffer springs 79 and 80, so that the fine movement from the connecting rod 16 is suppressed by the buffer springs 79 and 80 between the connecting rod 16 and the compensating piston 8. The fibrillation occurring in the compensating piston 8 can be made sufficiently small.

  That is, the play 72 and the elastic body are connected to the connecting portion of the force transmission path from the power piston 3 to the compensating piston 8 against the fine movement of the power piston 3 due to the hydraulic pressure fluctuation of the hydraulic oil from the control valve 5. By providing at least one of the buffer springs 79 and 80, the fibrillation suppression connecting structures 67A and 67B that suppress the fibrillation of the compensating piston 8 are provided. The amount of play 72 can be reduced by the width of the play 72 or through the buffer springs 79 and 80, and the fibrillation transmitted to the compensating piston 8 can be reduced.

  As described above, the initial gradually increasing port structure 66, 66A, 66B and the fibrillation suppression connecting structure 67A, 67B reduce the fibrillation in the power piston 3 and the compensating piston 8, respectively, thereby improving the jigling resistance. This improves the vibration of the link portion including the link mechanism 68, the output shaft 70, etc. interlocked with the power piston 3, thereby suppressing abnormal noise and stabilizing the engine operating state.

  The present invention relates to a power piston interlockingly connected to a fuel injection device of an engine, a control valve for switching a hydraulic oil path to the power piston by moving a spool in a sleeve provided with a control port, and the power piston. A compensating piston that is interlocked and connected via a connecting rod, and by moving the compensating piston, hydraulic pressure is applied to the spool to control the supply and discharge of hydraulic oil from the control port, and the power piston It can be applied to all hydraulic governors that suppress overshoot.

1 Hydraulic governor 3 Power piston 5 Control valve 6, 7, 79, 80 Buffer spring (elastic body)
8 Compensating piston 16 Connecting rod 17 Sleeve 17a Inner peripheral surface 18 Control port 22 Spool 28 Main control port 29/30 Sub control port 45 / 48a / 48b / 57a / 57b Predetermined distance 46 Spool moving direction 47/52/53 / 56 Open edge 55 Non-circular control port 56a Large open edge 56b / 56c Small open edge 58 Rod hole 60 Movable disk (first clamping member)
61 Movable ring (second clamping member)
66 / 66A / 66B Initial gradually increasing port structure 67A / 67B Fibrillation suppressing connecting structure 72 Play 73 Support portion S2 / S1 Area ratio

Claims (11)

  A power piston linked to the fuel injection device of the engine, a control valve for switching the oil passage of the hydraulic oil to the power piston by moving the spool land within the sleeve having the control port opened, and a connecting rod to the power piston And a compensating piston linked to each other through the movement of the compensating piston, and by controlling the supply and discharge of hydraulic fluid from the control port by applying hydraulic pressure to the spool by the movement of the compensating piston, the overshoot of the power piston In the hydraulic governor for suppressing the control valve, by providing a gradual increase area in which the change rate of the opening area with respect to the movement amount of the spool is small with respect to the fluctuation of the opening area of the control port due to the minute vibration of the control valve, Initial stage to suppress hydraulic pressure fluctuation of hydraulic oil to piston Hydraulic governor, characterized in that a multiplication port structure.   A plurality of substantially identical control ports are opened in the inner peripheral surface of the sleeve, and the opening edge of at least one control port of the control port is shifted by a predetermined distance in the spool moving direction from the opening edge of the other control port. The hydraulic governor according to claim 1, wherein the hydraulic governor is arranged.   The hydraulic governor according to claim 2, wherein the plurality of control ports are arranged so as to be continuously shifted in any one of the spool moving directions.   The hydraulic governor according to claim 2 or 3, wherein the predetermined distance is set to 40 µm or more.   A plurality of large-diameter main control ports and sub-control ports smaller than the main control port are opened on the inner peripheral surface of the sleeve, and the opening edge of the sub-control port is more open than the opening edge of the main control port. The hydraulic governor according to claim 1, wherein the hydraulic governor is disposed so as to protrude a predetermined distance in the spool moving direction.   The hydraulic governor according to claim 5, wherein an area ratio of the sub control port to the main control port is set to 10% or less.   The hydraulic governor according to any one of claims 1 to 6, wherein the control port is formed in a substantially circular shape in cross section.   At least one control port having a non-circular cross-sectional view is opened in the inner peripheral surface of the sleeve, and the opening edge of the control port includes a large opening edge having a large opening area and an opening having a small opening area. 2. The hydraulic governor according to claim 1, wherein the hydraulic governor is configured by a small opening edge portion, and the small opening edge portion is formed to protrude from the large opening edge portion by a predetermined distance in the spool moving direction.   A power piston linked to the fuel injection device of the engine, a control valve for switching the oil passage of the hydraulic oil to the power piston by moving the spool land within the sleeve having the control port opened, and a connecting rod to the power piston And a compensating piston linked to each other through the movement of the compensating piston, and by controlling the supply and discharge of hydraulic fluid from the control port by applying hydraulic pressure to the spool by the movement of the compensating piston, the overshoot of the power piston In a hydraulic governor that suppresses vibration, a play and an elastic body are connected to a connecting portion of a power transmission path from the power piston to the compensating piston against a fine movement of the power piston due to a hydraulic pressure fluctuation of hydraulic oil from the control valve. By interposing at least one of the Hydraulic governor, characterized in that a suppressing fibrillation suppressing connection structure fibrillation Se computing piston.   The connecting rod is slidably inserted into a rod hole in the power piston, and a pair of elastic bodies each having one end fixed in the rod hole are provided in the rod hole. The one sandwiching member and the second sandwiching member are arranged so as to be movable only in the separating direction while being biased in the approaching direction, and the connecting rod is interposed between the first sandwiching member and the second sandwiching member. The support part is interposed, and play is provided between at least one of the support part and the first clamping member or between the support part and the second clamping part. Hydraulic governor.   The connecting rod is slidably inserted into the compensating piston, and the front and rear side surfaces in the moving direction of the compensating piston are clamped in a biased state by the pair of elastic bodies whose one ends are fixed to the connecting rod. The hydraulic governor according to claim 9.

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