JP2010196798A - Valve structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve structure facilitating a assembling work while employing an independent port type valve disc. <P>SOLUTION: The valve structure is provided with: a shaft member 6; a valve disc 1 of an annular shape provided with a plurality of ports 2 disposed on an identical circumference and a valve seat 4 surrounding the circumference of an opening end of each of the ports 2 individually and attached around outer periphery of the shaft member 6; and a relief valve 5 of an annular shape and attached around the outer periphery of the shaft member 6 and opening or closing the ports 2. The relief valve 5 comprises a plurality of stacked annular plates 14, and a notch 15 opposite each of the ports 2 is formed in part or all of the annular plates 14. The shaft member 6 has a cross sectional shape other than a circular shape, and the annular plate 14 provided with the valve disc 1 and a notch 15, has an inner shape agreeing to the outer shape of the shaft member. The annular plate 14 provided with the valve disc 1 and the notch 15 is positioned in the circumferential direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an improved valve structure.

  Conventionally, this type of valve structure has been embodied, for example, as a damping valve on the extension side of a piston portion of a hydraulic shock absorber for a vehicle. Specifically, two pressure chambers are separated in the hydraulic shock absorber. And a piston provided with a plurality of ports provided on the same circumference, an annular window communicated therewith, and an annular valve seat provided on the outer periphery of the annular window, and laminated on the piston to the valve seat. Some include a leaf valve that opens and closes a port by opening and closing and a piston rod to which these are mounted.

  In this valve structure, in order to raise the damping force when the expansion speed of the hydraulic shock absorber is in the low speed range, each pressure chamber is communicated with an orifice or choke without separating the leaf valve from the valve seat. Specifically, the leaf valve is composed of a plurality of annular plates, and one or a plurality of annular plates are provided with notches that oppose the annular window and function as chokes and orifices, and each through the notches. The pressure chamber is communicated (see, for example, Patent Document 1).

  In the valve configured as described above, when the extension speed of the hydraulic shock absorber is in the low speed region as described above, the damping force can be raised by allowing the hydraulic oil to pass through the notch of the leaf valve. Therefore, good attenuation characteristics can be obtained in the low speed range.

JP 11-294515 A

  As described above, a good damping characteristic can be obtained with the conventional valve structure. However, since the valve seat is annular and each port communicates with a single annular window, the leaf valve is When the valve is opened from the seat, the entire circumference of the leaf valve is released from the valve seat all at once, and the port is opened. The damping coefficient greatly changes before and after the leaf valve is opened.

  On the other hand, by using a valve disk set as a so-called independent port type with a valve seat that individually surrounds the periphery of the open ends of multiple ports, the ports are opened all around the leaf valve. Instead of opening the ports by separating them from individual independent valve seats, the damping coefficient can be changed gently before and after the leaf valve is opened compared to a valve structure with an annular window. There are advantages.

  Therefore, if you want to enjoy this advantage, you would like to use an independent port type valve disc, but if you simply change the above-mentioned piston to an independent port type valve disc, the piston disc is assembled with a valve disc and a leaf valve. After attaching, the leaf valve notch and the port face each other, and the leaf valve is positioned with respect to the valve disc in the circumferential direction, and the extremely complicated assembly work of fixing them to the piston rod is forced. .

  Therefore, the present invention was created to improve the above-described problems, and the object of the present invention is to provide a valve structure that facilitates assembly work while employing an independent port type valve disk. It is to be.

  In order to solve the above-described object, the problem solving means in the present invention includes a shaft member, a plurality of ports arranged on the same circumference, and a valve seat that individually surrounds the open end of each port. In addition, the leaf valve is laminated in a valve structure including an annular valve disc mounted on the outer periphery of the shaft member and a leaf valve mounted on the outer periphery of the shaft member and opening and closing the port. It is composed of a plurality of annular plates, and a part or all of the annular plate is provided with a notch facing each port. An annular plate having a valve disk and a notch is positioned in the circumferential direction as a shape that matches the outer shape of the member.

  According to the valve structure of the present invention, the cross-sectional shape of the shaft member is a shape other than a circle, and the inner shape of the annular plate provided with the valve disk and the notch is matched with the outer shape of the shaft member. Since the annular plate is positioned in the circumferential direction, the notch of the annular plate automatically faces each port by attaching the annular plate with the valve disk and notch to the shaft member. Even if the valve disc set to be used is adopted, the assembly work for assembling the valve disc and the annular plate to the shaft member becomes very simple, and the work load is reduced.

It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve in one embodiment was embodied. It is a top view of the valve disc and leaf valve in which the valve in one embodiment was embodied. It is a top view of the leaf valve in which the valve in one modification of one embodiment was embodied.

  The valve structure of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, the valve structure in one embodiment is embodied in a damping valve on the extension side of the piston portion of the shock absorber, and includes a piston rod 6 as a shaft member, and a piston rod 6 A piston 1 serving as a valve disc having a plurality of ports 2 mounted on the outer periphery and arranged on the same circumference and a valve seat 4 surrounding each of the open ends of each port 2; An annular leaf valve 5 that is mounted on the outer periphery and stacked below the piston 1 in FIG. 1 and that is attached to and detached from the inner peripheral side of each valve seat 4 is configured.

  On the other hand, a shock absorber in which the valve of the present invention is embodied is well known and will not be described in detail, but specifically, for example, a cylinder 40 and a head member for sealing the upper end of the cylinder 40 (FIG. A piston rod 6 that slidably passes through a head member (not shown), a piston 1 that is a valve disk that is inserted into and fixed to the tip 7 of the piston rod 6, and a cylinder 40. An upper extension side chamber 41 and a lower pressure side chamber 42 in FIG. 1 separated by a piston 1 inside, a sealing member (not shown) that seals the lower end of the cylinder 40, and a piston that appears and disappears from the cylinder 40 A cylinder or an air chamber (not shown) that compensates for a change in the cylinder volume corresponding to the volume of the rod 6 is provided, and the cylinder 40 is filled with a fluid, specifically, for example, hydraulic oil.

  Further, in the valve structure, when the piston 1 moves upward in FIG. 1 with respect to the cylinder 40 and the fluid passes through the port 2 and moves from the expansion side chamber 41 to the compression side chamber 42, the fluid A resistance is applied to the flow by the leaf valve 5 to cause a predetermined pressure loss to generate a predetermined extension side damping force in the shock absorber.

  In addition to the above-described port 2, the piston 1 is provided with a plurality of ports 3 communicating with the extension side chamber 41 and the pressure side chamber 42, and the inner peripheral side of the port 3 is fixed to the tip 7 of the piston rod 6. 2 is opened and closed by an annular leaf valve 8 stacked on the end face of the piston 1 on the extension side chamber 41 side, and the piston 1 moves downward in FIG. When moving from the pressure side chamber 42 to the extension side chamber 41 through 3, a resistance is applied to the flow of the fluid by the leaf valve 8 to cause a predetermined pressure loss to generate a predetermined compression side damping force in the buffer. It is supposed to let you.

  Hereinafter, the valve will be described in detail. As shown in FIG. 1, the piston 1 serving as a valve disk is annular, and is opposite to the port 2 that allows fluid to pass from the expansion side chamber 41 to the compression side chamber 42. A port 3 that allows fluid to pass from the compression side chamber 42 to the extension side chamber 41.

  Further, in this case, a plurality of ports 2 and 3 are provided on the piston 1, and more specifically, four ports are provided as shown in the figure. The ports 2 are arranged at equal intervals on the same circumference. 3 are arranged at equal intervals on the same circumference, and the ports 2 and 3 are alternately arranged in the circumferential direction. The number of ports 2 and 3 can be set arbitrarily.

  Further, the piston 1 has an inner window portion 4a provided around the inner circumference through which the piston rod 6 is inserted, and an independent window which is an open end of the port 2 connected to the inner circumference seat portion 4a. 9 includes a petal-type valve seat 4 that protrudes toward the pressure side chamber 42 and has four surrounding portions 4b that individually surround the periphery of 9. Further, the piston 1 includes a petal-type valve seat 10 that individually surrounds the opening end of the port 3 on the extension side chamber 41 side. That is, the respective ports 2 and 3 in the piston 1 are individually surrounded by the valve seats 4 and 10 and are not communicated with each other, and are set to a so-called independent port type.

  The piston 1 which is the valve disc configured as described above has a leaf valve 8 and a valve stopper 11 stacked on the upper side in FIG. 1, a leaf valve 5 and a bending rigidity of the leaf valve 5 stacked on the lower side in FIG. 1. Along with the sub leaf valve 19 and the valve stopper 12 for adjusting the pressure, the piston rod 6 is assembled to the tip 7 and fixed to the piston rod 6 by the piston nut 13.

  The cross-sectional shape of the tip 7 of the piston rod 6 is a so-called D-shape obtained by cutting off a part of a circle, and the inner shape that is the inner shape of the piston 1 and the leaf valve 5 is the outer shape of the tip 7. When the tip 7 of the piston rod 6 is inserted into the inner periphery of the piston 1 and the leaf valve 5 and assembled to the tip 7 as described above, the piston 1 and the leaf valve 5 are moved in the circumferential direction. The piston 1 and the leaf valve 5 are non-rotatably attached to the piston rod 6.

  The outer shape of the tip 7 of the piston rod 6 and the inner shapes of the piston 1 and the leaf valve 5 corresponding to the outer shape are not limited to the D-shape described above, but when the piston 1 and the leaf valve 5 are mounted on the piston rod 6. As long as the piston 1 and the leaf valve 5 do not have to move relative to each other, any shape other than a circle may be used, but the strength of the tip 7 of the piston rod 6, the piston 1 and the leaf valve 5 is not significantly reduced. It is preferable to select a shape that does not support the screwing of the piston nut 13, and the D-shape or the two-sided width shape with both ends of the circle cut off may be used.

  The leaf valve 5 is formed by laminating two annular plates 14, and the annular plate 14 disposed at the uppermost position in FIG. 1 in contact with the valve seat 4 is as shown in FIG. Four notches 15 that face the four ports 2 are provided. In addition, a sub-leaf valve 19 configured by laminating a plurality of annular plates for adjusting the bending rigidity of the leaf valve 5 is laminated on the back surface on the side opposite to the piston of the leaf valve 5. The presence or absence of installation is optional.

  The notch 15 includes an arcuate facing portion 15a facing the port 2 and a communication portion 15b communicating from the outer periphery of the annular plate 14 to the facing portion 15a. The annular plate 14 having the notch 15 is connected to the piston 1. When the annular plate 14 that is not provided with the notch 15 is laminated on the annular plate 14, the port 2 communicates with the pressure side chamber 42 via the notch 15 in a state where the leaf valve 5 is seated on the valve seat 4. It is like that.

  In addition to the above, as shown in FIG. 3, the leaf valve 5 is constituted by three annular plates 14, and four ports are provided on the annular plate 14 disposed in the uppermost position in FIG. The four notches 16 functioning as two opposing orifices are provided, the annular plate 14 laminated thereon is provided with a notch 17 that opens from the outer periphery and faces the notch 16, and the annular plate 14 provided with the notch 17 The annular plate 14 may be laminated so that the port 2 communicates with the pressure side chamber 42 via the notch 16 and the notch 17 that function as an orifice, and the notch 16 and the notch 17 function as a passage. The diameter of the notch 16 may be increased so that the notch 17 functions as a choke passage instead of being used as an orifice.

  As described above, the plurality of annular plates 14 constituting the leaf valve 5 may be provided with notches so that the port 2 communicates with the pressure side chamber 42 while seated on the valve seat 4. Moreover, the outer diameter of the annular plate 14 provided with the notches 15, 16 and 17 and the annular plate 14 laminated thereon is the same.

  The inner shape of the annular plate 14 provided with the notches 15, 16, and 17 is a shape that matches the outer shape of the tip 7 of the piston rod 6, in this case, a D shape, and is attached to the tip 7 of the piston rod 6. Similarly, the notches 15, 16, and 17 are automatically opposed to the port 2 of the piston 1 that is positioned in the circumferential direction and similarly mounted on the tip 7 of the piston rod 6.

  Thus, by attaching the piston 1 and the leaf valve 5 to the tip 7 of the piston rod 6, the notches 15, 16, 17 provided in the leaf valve 5 are automatically opposed to the respective ports 2, so that the independent port type The piston 1 and the leaf valve 5 can be assembled easily to the piston rod 6 even when the piston 1 is used. Further, when the piston nut 13 is tightened, the piston 1 and the leaf valve 5 are relatively rotated. Since it is not necessary to hold it so as to prevent it, the work load is reduced also in this respect.

  The notches 15, 16 and 17 only have to face the port 2 of the piston 1, and the annular plate 14 not having the notches does not have any problem even if it rotates relative to the piston 1, so that the leaf valve 5 is configured. Only the inner shape of the annular plate 14 provided with the notches 15, 16, and 17 among the annular plates 14 should be matched with the outer shape of the tip 7 of the piston rod 6, and the inner shape of the annular plate 14 not provided with the notches is It may be circular. Further, the inner shape of the sub leaf valve 19 for adjusting the bending rigidity of the leaf valve 5 may be circular.

  Next, the operation of the valve configured as described above will be described. When the piston 1 moves upward in FIG. 1 with respect to the cylinder 40, the pressure in the extension side chamber 41 increases, and the fluid in the extension side chamber 41 passes through the port 2 and tends to move into the pressure side chamber 42.

  In the stroke in which the shock absorber extends in this way, a force to push the leaf valve 5 upward in FIG. 1 acts, but when the piston speed is in the low speed region, the pressure in the extension side chamber 41 is small, The leaf valve 5 does not flex and remains seated on the valve seat 4.

  Then, in such a state, the extension side chamber 41 and the pressure side chamber 42 are brought into communication with each other via the notch 15 provided in the leaf valve 5, so that the fluid is compressed via the extension side chamber 41, the port 2 and the notch 15. When the damping force is generated by the resistance when moving to the chamber 42 and passing through the notch 15 and the piston speed is in the low speed region during the extension stroke of the shock absorber, the damping characteristic is as follows. It becomes a characteristic that the attenuation coefficient increases.

    On the other hand, when the piston speed increases and reaches the high speed region, the pressure in the extension side chamber 41 becomes large and the leaf valve 5 is bent together with the sub leaf valve 19. Since the port 2 is opened after being separated, the damping coefficient is smaller than that in the low speed region described above, but since the independent port type piston 1 is adopted, the piston speed is low and high. The damping coefficient of the shock absorber does not change suddenly at the border of the vehicle, and the damping coefficient changes slowly. Especially when the shock absorber is applied to a vehicle, it makes the vehicle passenger feel a shock or feel uncomfortable. The ride comfort in the vehicle can be improved.

  In the above description, the valve structure of the present invention has been described using an example embodied in the damping valve on the expansion side of the piston portion of the shock absorber. Of course, it can also be embodied in the base valve unit, and can be applied to a valve that functions as a damping force generating element that generates a damping force. .

 This is the end of the description of the embodiment of the valve structure of the shock absorber, but the scope of the present invention is not limited to the details shown or described.

The valve structure of the present invention can be applied to a shock absorber valve.

DESCRIPTION OF SYMBOLS 1 Piston 2, 3 Ports 4, 10 which are valve discs Valve seat 4a Inner peripheral seat part 4b in valve seat Enclosed part 5 in valve seat Leaf valve 6 Piston rod 7 Piston rod tip 8 Leaf valve 9 Independent window 11, 12 Valve stopper 13 Piston nut 14 Annular plates 15, 16, 17 Notch 15a Opposing portion 15b Communication portion 19 Sub leaf valve 40 Cylinder 41 Extension side chamber 42 Pressure side chamber

Claims (1)

A valve disk having a shaft member, a plurality of ports arranged on the same circumference, and a valve seat that individually surrounds the periphery of the open end of each port, and being annular and mounted on the outer periphery of the shaft member; In a valve structure that is annular and has a leaf valve that is attached to the outer periphery of the shaft member and that opens and closes the port, the leaf valve is composed of a plurality of annular plates, and each port is provided in part or all of the annular plate The shaft member has a cross-sectional shape other than a circular shape, and the inner shape of the annular plate including the valve disk and the notch matches the outer shape of the shaft member. A valve structure characterized by positioning a plate in a circumferential direction.

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