KR20070122392A - Spool valve device - Google Patents

Abstract

A spool valve device is provided to make a vale small and light-weight by reducing entire length in addition to hold a spool with rotating a stop state. A spool valve device includes a valve housing(12), a spool(21), left and right covers, a rotating stop member(35). The valve housing has a plurality of oil pathways connected with a spool slide movement hole. The spool is inserted in the spool slide movement hole of the valve housing and connects and intercepts between a plurality of oil pathways. The left and right covers form pilot oil chambers(29A,29B) which drive the spool toward a shaft. The rotating stop member controls that the spool rotates inside the spool slide movement hole. The rotating stop member has an operation guide(36) that moves through the spool toward the shaft. The operation guide is installed between any one of the left and right covers and the spool and fits in the any one of the left and right covers in a stopping state.

Description

Spool Valve Unit {SPOOL VALVE DEVICE}

1 is a longitudinal sectional view showing a direction control valve for a hydraulic cylinder according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing the cover, the protruding shaft portion of the spool, the movable guide, the spring, and the like in FIG.

Figure 3 is a perspective view of the movable guide in Figure 2 seen from the opposite side.

4 is a front view of the movable guide shown in FIG.

Fig. 5 is a sectional view of the movable guide viewed from the arrow V-V direction of Fig. 4;

Fig. 6 is a longitudinal sectional view at the same position as in Fig. 1 showing a state in which the spool of the directional control valve is stroked in the right direction.

Fig. 7 is a longitudinal sectional view at the same position as in Fig. 1 showing a state in which the spool of the directional control valve is stroked in the left direction.

Fig. 8 is an enlarged view of the essential portion of Fig. 1 showing the projection shaft portion, the movable guide, the spring and the like when the spool is in the neutral position.

Fig. 9 is an enlarged view of an essential part of Fig. 6 showing the protruding shaft portion, the movable guide, the spring, and the like when the spool is stroked in the right direction.

Fig. 10 is an enlarged view of an essential part of Fig. 7 showing the protruding shaft portion, the movable guide, the spring, and the like when the spool is stroked in the left direction.

Fig. 11 is an enlarged cross sectional view showing a protruding shaft portion and a lid for stopping rotation of a spool according to a comparative example.

12 is an enlarged sectional view showing the rotation preventing mechanism according to the second embodiment in a state where the spool is in a neutral position.

Fig. 13 is an enlarged sectional view showing the rotation preventing mechanism according to the third embodiment in a state where the spool is in a neutral position.

Fig. 14 is an enlarged sectional view showing the rotation preventing mechanism according to the fourth embodiment in a state where the spool is in a neutral position.

Fig. 15 is an exploded perspective view showing the protruding shaft portion and the movable guide of the rotation preventing mechanism according to the fifth embodiment.

<Explanation of symbols for the main parts of the drawings>

1: hydraulic pump

2: tank

5: hydraulic cylinder

11: directional control valve (spool valve device)

12: valve housing

13: spool sliding hole

14A, 14B, 16A, 16B, 17A, 17B: Oil Groove (Oil Passage)

15: connection passage (oil passage)

18A, 18B: Pressure oil supply and distribution path (oil passage)

19: high pressure passage

20: check valve

21: spool

25, 61, 71: protrusion shaft

25A, 61A, 71A: Chamfer

26: step surface (end surface of the spool)

27A, 27B: Cover

27Al: Flat surface part

28A, 28B: Connection port

29A, 29B: Pilot Oil Seal

32: return spring

35, 41, 51, 63, 73: rotation prevention mechanism (rotation stop means)

36, 42, 72: operation guide

36A, 42A, 72A: Bending plate part

36B, 42B, 72B: guide hole

36C, 42C, 72C: inner plate part

37, 43: spring

52: fall prevention plate (fall prevention member)

53: Bolt

61C: Annular Groove

62: stop wheel (fall prevention member)

71B: Fall prevention protrusion (fallout prevention member)

[Document 1] Japanese Unexamined Patent Publication No. Hei 8-61521

[Document 2] Japanese Unexamined Patent Publication No. Hei 8-219300

The present invention relates to, for example, a spool valve device which is installed in a construction machine such as a hydraulic shovel and is suitably used as a direction control valve, a pressure control valve or a flow control valve.

In general, in construction machines such as hydraulic shovels, for example, to supply pressure oil from a hydraulic source such as a hydraulic pump to a hydraulic actuator (for example, a hydraulic motor, a hydraulic cylinder, etc.), the hydraulic actuator and the hydraulic source are interposed therebetween. A spool valve device such as a directional control valve is provided.

The spool valve device according to the prior art of this kind is provided with a valve housing provided with a spool sliding hole and a plurality of oil passages communicating with the spool sliding hole, and inserted into the spool sliding hole of the valve housing. Left and right lids for spools communicating and blocking between oil passages, spools disposed on both sides of the spool in the axial direction and provided in the valve housing to form pilot oil chambers for axially driving the spool therein; It is provided with the cover of any one of the right cover, and is provided with the rotation stop member which suppresses that the said spool rotates in a spool sliding hole (for example, refer document 1, 2).

In other words, lands for communicating with and blocking the respective oil passages are formed in the spool valve device on the outer circumferential side of the spool, and notches made of so-called cutouts are formed in the lands. When the oil passages communicate with each other through the notches, the pressure oil passes through the notched state, so that the spool is subjected to a rotational force about the shaft center under the influence of the flow velocity or the flow direction. have.

As a result, when the spool rotates, the spool itself or the spool sliding hole of the valve housing into which the spool is fitted may be worn and damaged at an early stage. Therefore, rotation stops between the cover and the spool provided on one side of the valve housing. A member is provided, and the rotation stop member is slid-contacted to the chamfer part which consists of flat surfaces provided in the axial direction side of the spool, for example, and it is set as the structure which restricts rotation of a spool (rotation stop).

By the way, in the above-mentioned prior art, for example, the rotation stop member is fixed to the inner circumferential side of the lid, and the rotation stop member is slidingly contacted with the flat chamfer provided on one side of the spool. It is necessary to form the portion in a length that spans the entire stroke length, and there is a problem that the total length dimension of the spool valve device becomes excessively large.

That is, the spool installed in the spool sliding hole of the valve housing is slidably displaced with the stroke length L from the neutral position to the left direction, and slid with the stroke length L from the neutral position to the right direction. Is displaced. For this reason, it is necessary to form the chamfer of a spool longer than the length (2 * L) which can be stroked in the left and right directions from a neutral position (for example, refer the comparative example shown in FIG. 11).

In addition, the cover surrounding the chamfer from the outside always has a gap between the end face of the spool (end face on the side of the chamfer) even when the spool is stroked in the direction in which the spool enters the cover (for example, the left direction). Since it is necessary to form, the axial length of a cover needs to be formed at least longer than a dimension (3 * L).

As a result, the spool valve device of the type which stops rotation (rotation stop) of the spool has an extra long overall length including the cover, compared to the spool valve device of the type that does not stop the rotation. There is a problem that it cannot be realized.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is not only to keep the spool in a rotational stop state, but also to shorten the overall length of the spool so that the compactness and the weight can be realized. A valve device is provided.

MEANS TO SOLVE THE PROBLEM In order to solve the above-mentioned subject, this invention provides the valve housing provided with the spool sliding hole and the some oil passage which communicates with the said spool sliding hole, and the said oil passage inserted in the spool sliding hole of the said valve housing. Left and right lids for spools communicating and blocking between the spools, spools disposed on both sides of the spool in the axial direction and installed in the valve housing to form a pilot oil chamber therein for axially driving the spools; It is applied to the spool valve apparatus provided in the cover side of either cover and provided with the rotation stop means which suppresses the said spool to rotate in a spool sliding hole.

A feature of the configuration employed by the invention of claim 1 is that the rotation stop means is positioned between the one cover and the spool, fitted in the rotation stop state in the cover, and simultaneously follows the spool in the axial direction. It is what comprised by the movable operation guide.

According to the invention of claim 2, the spool is provided with a protruding shaft portion protruding in the axial direction from the end face on one side in the axial direction toward the inside of the one lid, the movable guide being inserted in the rotation stop state, and the lid And a spring for constantly pressing the movable guide toward the end face of the spool and holding the movable guide in a fall prevention state between the and the movable guide.

On the other hand, according to the invention of claim 3, the protruding shaft portion protrudes in the axial direction from the end surface on one side in the axial direction toward the inside of the cover, and is provided with a protruding shaft portion into which the movable guide is inserted in the rotation stop state. At the tip end side of the shaft portion, a release preventing member for holding the movable guide in a release preventing state is provided.

According to the invention of claim 4, a flat chamfer extending in the axial direction is provided on the protruding shaft portion of the spool, and a flat surface portion is provided on the inner circumferential side where the pilot oil chamber is formed on the one cover, and the movable The guide is configured to be maintained in the rotation stop state by the chamfer portion of the protruding shaft portion and the flat surface portion of the lid.

EMBODIMENT OF THE INVENTION Hereinafter, the case where the spool valve apparatus which concerns on embodiment of this invention is applied to the direction control valve for hydraulic cylinders is taken as an example, and it demonstrates in detail according to an accompanying drawing.

1 to 10 show a first embodiment of the present invention. In the figure, reference numeral 1 denotes a hydraulic pump constituting a hydraulic source together with the tank 2, and the hydraulic pump 1 is driven by rotation by a prime mover (not shown) of a hydraulic shovel, for example. The hydraulic oil sucked in from the inside is discharged into the pump conduit 3 as high pressure oil. The pressure oil discharged in the pump pipe line 3 is supplied to the hydraulic cylinder 5 or the like via the directional control valve 11 or the like described later, and the return oil from the hydraulic cylinder 5 is supplied from the directional control valve 11 side. It is discharged to return to the tank 2 via the tank conduit (4).

Reference numeral 5 denotes a working hydraulic cylinder that constitutes a hydraulic actuator, and the hydraulic cylinder 5 constitutes, for example, a boom cylinder, an arm cylinder, a bucket cylinder, or the like installed in a working device (not shown) of the hydraulic shovel. And the hydraulic cylinder 5 is divided into two oil chambers 8A and 8B by the piston 7 in the tube 6, and the rod 9 in which the base end side was fixed to the piston 7 is the front end side. It protrudes out of the tube 6.

Reference numerals 10A and 10B denote a pair of supply and discharge lines connected to the oil chambers 8A and 8B of the hydraulic cylinder 5, and the supply and discharge lines 10A and 10B are, for example, by hydraulic piping such as a flexible hose. It is comprised and is connected to the hydraulic oil supply passage 18A, 18B of the valve housing 12 mentioned later. And supply-discharge pipe lines 10A and 10B supply and distribute the pressure 9 from the hydraulic pump 1 to the hydraulic cylinder 5 via the direction control valve 11 etc. which are mentioned later, and thereby the load 9 of the hydraulic cylinder 5 is loaded. It expands and contracts from the tube 6.

Reference numeral 11 denotes a direction control valve as a spool valve device provided between the hydraulic pump 1, the tank 2, and the hydraulic cylinder 5, and the direction control valve 11 is a valve housing 12 and a spool 21 to be described later. ), Lids 27A, 27B and the like. And the direction control valve 11 slides the spool 21 from the neutral position shown in FIG. 1 to the switching position shown in FIG. 6, 7, respectively, and the direction of the hydraulic oil supplied to the hydraulic cylinder 5 is displaced. To switch.

Reference numeral 12 denotes a valve housing constituting the valve body of the directional control valve 11, the valve housing 12 includes a spool sliding hole 13 extending in left and right directions as shown in FIG. The left and right oil grooves 14A and 14B, which are spaced apart in the axial direction of the spool sliding hole 13 and formed as annular grooves on the peripheral wall side of the spool sliding hole 13, form an inverted U-shape as a whole. The communication passage 15 etc. which the both ends of the right side communicate with the spool sliding hole 13 through oil groove 14A, 14B are provided.

The valve housing 12 is also provided with other oil grooves 16A and 16B at positions that are axially outward from the oil grooves 14A and 14B on the peripheral wall side of the spool sliding hole 13. Other oil grooves 17A, 17B and the like are provided at positions that become outside in the axial direction from those of 16A and 16B. These oil grooves 17A and 17B are connected to the tank 2 via the tank conduit 4, respectively, and constitute an oil passage on the tank side (oil passage on the hydraulic pressure source side).

On the other hand, the valve housing 12 is located at both the left and right sides of the spool sliding hole 13, and the sealing spot facing surfaces 12A and 12B have a depth as shown in Figs. It is formed as a shallow concave surface, and the O-ring 38 mentioned later is located in the spot facing surfaces 12A and 12B, and is located between the lids 27A and 27B.

In addition, the valve housing 12 is provided with a cylindrical projection 12C projecting from the position of the spot facing surface 12B toward the inside of the lid 27B to be described later, as shown in FIGS. 1, 6, and 7. On the outer circumferential side of the cylindrical projection 12C, the proximal end side of the lid 27B is fitted and installed. Here, the inner periphery of the cylindrical projection 12C constitutes a part of the spool sliding hole 13. And this cylindrical support part 12C contacts the spring support 33 mentioned later, for example, when the spool 21 mentioned later slides and displaces leftward, as shown in FIG. The spring force of the return spring 32 is received via (33).

Reference numerals 18A and 18B denote left and right pressure oil supply and discharge paths provided in the valve housing 12, and the pressure oil supply and discharge paths 18A and 18B are left and right oil grooves 16A and 16B on the peripheral wall side of the spool sliding hole 13. ), And together with these oil grooves 16A and 16B, it constitutes an oil passage on the actuator side. The hydraulic oil supply and demand passages 18A and 18B are connected to the oil chambers 8A and 8B of the hydraulic cylinder 5 via the supply and delivery conduits 10A and 10B.

Reference numeral 19 denotes a high pressure passage provided in the valve housing 12, and the high pressure passage 19 is connected to the hydraulic pump 1 via a pump conduit 3, as indicated by a dotted line in FIG. ), The pressure oil discharged is supplied. The high pressure passage 19 is provided with a check valve 20 between the communication passages 15.

Here, the check valve 20 permits the pressure oil to flow from the high pressure passage 19 toward the communication passage 15 and prevents the flow in the reverse direction. Then, the communication passage 15 is connected to the high pressure passage 19 via the check valve 20, thereby forming the oil passage on the pump side (oil passage on the hydraulic pressure side) together with the left and right oil grooves 14A and 14B. It is.

Reference numeral 21 denotes a spool of the directional control valve 11, and the spool 21 is inserted into the spool sliding hole 13 of the valve housing 12 and supplied to the pilot oil chambers 29A and 29B to be described later. According to this, the inside of the spool sliding hole 13 is slid and displaced in the left and right directions. The spool 21 is provided with a pair of switching lands 22A and 22B spaced apart from the axial middle part (center part) to both the left and right sides.

The switching land 22A on the left side of the switching lands 22A and 22B blocks the oil grooves 14A and 16A when the spool 21 is in the neutral position as shown in FIG. As shown in FIG. 6, when the spool 21 is displaced from the neutral position to the right direction, the oil grooves 14A and 16A are communicated. In addition, the switching land 22B on the right side cuts off the oil grooves 14B and 16B when the spool 21 is in the neutral position as shown in FIG. 1, and as shown in FIG. 7, the spool 21. ) Is in communication with the oil grooves 14B and 16B when it is displaced to the left side from the neutral position.

Reference numerals 23A and 23B are left and right end lands provided on both end sides of the spool 21, and the end lands 23A and 23B are provided at positions spaced left and right away from the switching lands 22A and 22B. The notches 24A and 24B which consist of what is called a notch part are formed in the side. The end lands 23A and 23B communicate and block the oil grooves 16A and 16B on the actuator side and the oil grooves 17A and 17B on the tank side via the notches 24A and 24B.

That is, when the spool 21 is displaced from the neutral position to the left side as shown in Fig. 7, the oil groove 16A on the actuator side is the end land 23A and the notch 24A on the oil groove 17A on the tank side. Communicate via). Thereby, the return oil discharged | emitted from the oil chamber 8A of the hydraulic cylinder 5 carries out the hydraulic oil supply line 18A, the oil groove 16A, the end land 23A, the notch 24A, and the oil groove 17A. It is refluxed (discharged) to the tank 2 side via.

In addition, when the spool 21 is displaced in the right direction as shown in Fig. 6, the oil groove 16B on the actuator side passes through the end land 23B and the notch 24B through the oil groove 17B on the tank side. Communicate. Thereby, the return oil discharged | emitted from the oil chamber 8B of the hydraulic cylinder 5 is the hydraulic oil supply and drain path 18B, the oil groove 16B, the end land 23B, the notch 24B, the oil groove 17B. It is refluxed (discharged) to the tank 2 side via the via.

Reference numeral 25 denotes a protruding shaft portion protruding in the axial direction from the left end surface of the spool 21, and the protruding shaft portion 25 is integrally formed on the end land 23A side of the spool 21, and the lid 27A described later. Protrude with dimension H (see FIG. 8) in the axial direction. The axial length [dimension H] of the protruding shaft portion 25 is, for example, the stroke length L when the spool 21 is slidably displaced from the neutral position in the right direction (or the left direction). About FIG. 9, as shown in following formula 1, it is formed as long as dimension (a) (for example, a = 1-3 mm). In addition, the total stroke length when the spool 21 is stroked in both the left and right directions from the neutral position is set to a dimension equal to (2 × L).

[Equation 1]

H = L + a

Here, as shown in Fig. 2, for example, chamfers 25A and 25A made of flat surfaces are formed in the protruding shaft portion 25 so as to face each other, and each of the chamfers 25A protrudes. It extends parallel to each other over the entire length of the shaft portion 25. This chamfer 25A constitutes a non-circular sliding part, and allows the movable guide 36 to be relatively displaced in the axial direction while rotating the movable guide 36 to be described later.

Reference numeral 26 is an annular stepped surface located between the protruding shaft portions 25 and formed on the end surface of the spool 21, and the stepped surface 26 is the left end of the end land 23A as shown in FIG. A bottom surface is formed and the movable guide 36 mentioned later is contacted in surface contact state. In addition, when the spool 21 is largely stroked in the right direction as shown in Fig. 9, the stepped surface 26 is spaced apart from the end face of the movable guide 36 in the axial direction.

Reference numerals 27A and 27B are left and right lids that constitute the direction control valve 11 together with the spool 21, and the lids 27A and 27B are axial directions (left and right directions) of the spool sliding hole 13. It is located on both sides and is detachably fixed to the valve housing 12, and closes both ends of the spool sliding hole 13. Moreover, connection ports 28A, 28B, such as pilot piping (not shown), are provided in the cover 27A, 27B, and one connection port 28A of these connection ports 28A, 28B is provided, for example. As shown in Fig. 8, the film has a dimension L1 in the axial direction.

In addition, the pilot oil chambers 29A and 29B are formed in the lids 27A and 27B in communication with the connection ports 28A and 28B. For example, the hydraulic shovels are provided in the pilot oil chambers 29A and 29B. Pilot pressure is supplied from a remote control valve (not shown), such as a pressure reducing valve type pilot valve, in which an operator is manually operated. The spool 21 of the directional control valve 11 is slidably displaced in the spool sliding hole 13 in the left and right directions according to the pilot pressure at this time.

Here, the cover 27A on the left side of the cover 27A, 27B on the left and right sides is opposite to the peripheral wall (inner circumference) side in which the pilot oil chamber 29A is formed, as shown in FIG. Flat surface parts 27Al and 27Al are provided, and the movable guide 36 mentioned later is fitted in these flat surface parts 27Al in a rotation stop state. As shown in Fig. 8, the lid 27A on the left side has a length Lt in the axial direction, and the dimension Lt is the pilot oil chamber 29A as shown in Equation 2 below. It is set as the total value of the dimension L2 of and the dimension L1 of the connection port 28A.

[Equation 2]

Lt = L1 + L2

On the other hand, among the left and right lids 27A and 27B shown in FIG. 1, the lid 27B located on the right side is formed longer than the lid 27A on the left side. In the lid 27B on the right side, a spring chamber 30, a stopper shaft 31, a return spring 32, spring supports 33, 34, and the like, which are described later, are provided. Further, as shown in Fig. 1, the lid 27B is provided with an annular stepped portion 27Bl to which the end of the spring rest 34 contacts.

Reference numeral 30 denotes a spring chamber provided in the lid 27B, and the spring chamber 30 has a cylindrical projection 12C and a lid 27B of the valve housing 12 as shown in Figs. 1, 6 and 7. It is formed as an annular space in the lid 27B located between the stepped portions 27Bl. In the spring chamber 30, a return spring 32 to be described later is disposed in a compressed state via the stopper shaft 31 and the spring supports 33 and 34. In addition, the spring chamber 30 communicates with the pilot oil chamber 29B at the head portion 31B side of the stopper shaft 31, which will be described later, and the pilot pressure in the pilot oil chamber 29B is also introduced into the spring chamber 30. It is derived.

Numeral 31 denotes a stopper shaft screwed to the right end of the spool 21. The stopper shaft 31 has one threaded portion 31A screwed onto the spool 21, and a spring chamber of the lid 27B. 30) It extends in the axial direction. In addition, the other side of the stopper shaft 31 becomes a hexagonal head portion 31B inserted with a gap in the lid 27B, and the head portion 31B pilot oils the spring chamber 30 in the lid 27B. It communicates with the yarn 29B at the outer peripheral side. The stopper shaft 31 restricts the stroke end when the spool 21 is slidably displaced in the right direction, for example, as shown in FIG.

Reference numeral 32 denotes a return spring for holding the spool 21 in a neutral position. The return spring 32 is inserted through the spring supports 33 and 34 on the outer circumferential side of the stopper shaft 31, and the spool 21 ) Is disposed in a state in which an initial load is applied in advance between the end face (end face of cylindrical protrusion 12C) and stopper shaft 31 (step 27Bl of lid 27B). The return spring 32 holds the spool 21 in the neutral position when the pressure (pilot pressure) in the pilot oil chambers 29A and 29B drops to the tank pressure level.

On the other hand, the return spring 32 is the right end surface and the lid 27B of the spool 21 when the spool 21 is slidably displaced in the right direction as shown in Fig. 6 by the pilot pressure from the connection port 28A. Compression is deformed between the stepped portions 27Bl. In addition, when the spool 21 is slidably displaced in the left direction as shown in FIG. 7 by the pilot pressure from the connection port 28B, the end face of the cylindrical projection 12C and the end face of the head 31B are separated. The return spring 32 is compressively deformed in between.

Reference numeral 35 denotes a rotation prevention mechanism as a rotation stop means provided between the lid 27A on the left side and the projection shaft portion 25 of the spool 21, and the rotation prevention mechanism 35 is a chamfer of the projection shaft portion 25 described above. It is comprised by the flat surface part 27Al of the base 25A and the cover 27A, the movable guide 36, and the spring 37 which are mentioned later. The rotation prevention mechanism 35 restricts the rotation of the spool 21 about the shaft center in the spool sliding hole 13 of the valve housing 12.

Reference numeral 36 is a movable guide provided between the lid 27A and the protruding shaft portion 25. The movable guide 36 is formed by bending a metal plate as shown in Figs. The lower bent plate portions 36A and 36A form a flat surface shape. In addition, a guide hole 36B corresponding to the outer shape of the protruding shaft portion 25 is punched in the inner circumferential side of the movable guide 36, and inner plate portions 36C having a flat surface shape above and below the guide hole 36B, 36C) is bent and formed in the same direction as the bending plate part 36A.

Here, each bending plate part 36A of the movable guide 36 is formed in the dimension substantially equal to the axial length (dimension H) of the protrusion shaft part 25, as shown in FIG. Is fitted to the flat surface portion 27Al in the rotation stop state or is in sliding contact (see Fig. 2). In addition, each inner plate portion 36C of the movable guide 36 has a smaller projecting dimension (bending dimension) in the axial direction than the bending plate portion 36A.

Each inner plate portion 36C of the movable guide 36 is in sliding contact with the chamfer 25A in a state of being in surface contact with the guide hole 36B being inserted into the protruding shaft portion 25. Thereby, the guide hole 36B and each inner plate part 36C of the movable guide 36 are controlled in the axial direction while restricting the protruding shaft portion 25 (spool 21) from rotating relative to the movable guide 36. To allow relative movement (displacement).

Moreover, the movable guide 36 is urged by the spring 37 mentioned later so that it may contact the step surface 26 of the spool 21 in surface contact state. When the spool 21 is largely stroked in the right direction as shown in Fig. 9, the outer circumferential side of the movable guide 36 is in contact with the spot facing surface 12A of the valve housing 12, and the movable guide ( 36 is axially spaced from the step surface 26 of the spool 21.

Reference numeral 37 is a spring constituting the holding member of the rotation preventing mechanism 35, and the spring 37 is configured using, for example, a weak spring having a small pressing force, and as shown in Figs. 6 to 10. It is arrange | positioned in the state which was bent deformation (elastic deformation) between the bottom part of the cover 27A and the movable guide 36 previously.

And the spring 37 has the step surface which makes the movable guide 36 an end surface of the spool 21 in order to hold | maintain the guide hole 36B of the movable guide 36 in the state which inserted in the protrusion shaft part 25. As shown in FIG. It always presses toward 26, and permits the movable guide 36 to be axially displaced along the chamfer 25A of the protruding shaft portion 25. As shown in FIG.

Reference numerals 38 and 38 denote O-rings as sealing members for sealing between the valve housing 12 and the lids 27A and 27B, and the O-rings 38 are valves as shown in Figs. 1, 7, 9 and the like. It is arrange | positioned in the spot facing surfaces 12A and 12B of the housing 12, and is mounted in the liquid-tight state between this spot facing surfaces 12A and 12B and the lid | cover 27A and 27B.

The direction control valve (spool valve device) for the hydraulic cylinder 5 which concerns on this embodiment has the structure as mentioned above, and its operation | movement is demonstrated next.

First, the pilot oil chambers 29A and 29B in the lids 27A and 27B provided on both the left and right sides of the directional control valve 11 are, for example, a pressure reducing valve type pilot valve that the operator of the hydraulic shovel operates manually. Pilot pressure is supplied from the remote control valve through the pilot pipe (not shown) and the connection ports 28A and 28B.

When the pilot pressure at this time falls to the level of the tank pressure, the spool 21 is returned to the neutral position by the return spring 32 as shown in FIG. The installed left and right pressure oil supply and drain paths 18A and 18B are cut off from the oil grooves 14A and 14B by the switching lands 22A and 22B of the spool 21 and at the same time, the oil is supplied by the end lands 23A and 23B. It is also blocked from the grooves 17A and 17B.

For this reason, the oil chambers 8A, 8B of the hydraulic cylinder 5 are cut off from the hydraulic pump 1 (high pressure pipeline 19), and also from the tank 2 (tank pipeline 4), The rod 9 of the hydraulic cylinder 5 is not stretched from the tube 6 and remains stationary.

Next, for example, the operator of the hydraulic shovel tilts the operating lever of the remote control valve to operate the hydraulic cylinder 5, and pilots it in the pilot oil chamber 29A on the lid 27A side, for example. When the pressure is supplied, the spool 21 is slidably displaced in the right direction against the return spring 32 as shown in Fig. 6, and the oil grooves 14A and 16A (contact passages) are switched by the switching land 22A. 15 and the hydraulic oil supply and discharge path 18A are communicated with each other. In addition, the end land 23B of the spool 21 communicates with the oil grooves 16B and 17B (the pressure oil supply and discharge path 18B and the tank conduit 4) via the notches 24B and the like.

As a result, the oil pressure from the hydraulic pump 1 flows into the oil chamber 8A of the hydraulic cylinder 5 from the high pressure pipe 19, the check valve 20, the communication passage 15, the hydraulic oil supply and drain path 18A, and the gas supply. It is supplied via the conduit 10A, and the return oil from the oil chamber 8B is supplied from the tank conduit 4 via the supply / discharge line 10B, the pressure oil supply / discharge line 18B, the notch 24B of the spool 21, and the like. It is discharged into the tank 2. As a result, the rod 9 of the hydraulic cylinder 5 is driven in the arrow A direction (extension direction) in FIG.

On the other hand, when the operating lever of the remote control valve is inclined in the opposite direction from the neutral position and the pilot pressure is supplied into the pilot oil chamber 29B on the lid 27B side, for example, the spool 21 is shown in FIG. As described above, the sliding spring is displaced in the left direction against the return spring 32, and the switching land 22B communicates with the oil grooves 14B and 16B (the contact passage 15 and the hydraulic oil supply and discharge path 18B). do. The end lands 23A of the spool 21 communicate with the oil grooves 16A and 17A (the pressure oil supply and drain path 18A and the tank conduit 4) via the notches 24A and the like.

As a result, the oil pressure from the hydraulic pump 1 flows into the oil chamber 8A of the hydraulic cylinder 5 from the high pressure pipe 19, the check valve 20, the communication passage 15, the pressure oil supply and drain path 18B, and the supply / discharge. It is supplied via the conduit 10B, and the return oil from the oil chamber 8A is supplied from the tank conduit 4 via the supply / discharge line 10A, the pressure oil supply / discharge line 18A, the notch 24A of the spool 21, and the like. It is discharged into the tank 2. As a result, the rod 9 of the hydraulic cylinder 5 is driven in the arrow B direction (reduction direction) in FIG.

By the way, when the spool 21 of the directional control valve 11 is slidably displaced (switched) from the neutral position to the left and right directions, for example, the return oil from the hydraulic cylinder 5 is The notches 24A, 24B provided on the end lands 23A, 23B, and the like are flowed into the sorted state at a relatively high speed.

For this reason, the spool 21 may be subjected to a rotational (rotating) force about the shaft center by being affected by the flow rate or the flow direction of the oil liquid passing through the notches 24A or 24B. Rotation in the spool sliding hole 13 causes both sliding surfaces and the like to wear out prematurely and become damaged, resulting in deterioration of the durability and life of the apparatus.

So, in this embodiment, the rotation prevention mechanism 35 as a rotation stop means is provided between 27 A of lids of the left side, and the protruding shaft part 25 of the spool 21, and the spool sliding hole of the valve housing 12 ( 13) The rotation prevention mechanism 35 restricts the rotation of the spool 21 in the chamber.

The anti-rotation mechanism 35 includes a chamfer portion 25A formed of a flat surface formed on the outer circumference of the protruding shaft portion 25, a flat surface portion 27Al formed on the inner circumferential surface of the lid 27A, and a bending on the outer circumferential side. A movable guide having a guide hole 36B on which the plate portion 36A is fitted to the flat surface portion 27Al or is in sliding contact with the chamfered portion 25A of the protruding shaft portion 25 on the inner circumferential side so as to be relatively displaceable. 36 and the spring 37 which holds the guide hole 36B of the movable guide 36 in the state which inserted in the protrusion shaft part 25. As shown in FIG.

Thus, when the spool 21 is stroked in the right direction from the neutral position as shown in Figs. 6 and 9, the guide hole 36B of the movable guide 36 moves the protruding shaft portion 25 of the spool 21 to the right. The sliding displacement (relative displacement) in the axial direction with respect to the axial direction, and the chamfer 25A of the protruding shaft portion 25, the guide hole 36B of the movable guide 36, and the inner plate portion 36C are slid in a rotating stop state. By the moving contact, the rotation of the spool 21 can be stopped.

In addition, by pressing the movable guide 36 against the step surface 26 of the spool 21 with the spring 37, the movable guide 36 can be maintained in the inserted state in the protruding shaft portion 25, and the movable guide The 36 can be prevented from being discharged from the tip end side of the protruding shaft portion 25.

For this reason, the stroke length L when the axial length [dimension H] of the protrusion shaft part 25 is slidably displaced to the right direction from a neutral position, for example (refer FIG. 9). With respect to the length (a) (for example, a = about 1 to 3 mm) shown in the above formula (1), the ejection of the movable guide 36 can be prevented, and the protruding shaft portion 25 can be prevented. By using the movable guide 36, the dimension H can be shortened to a length substantially equal to the stroke length L.

In addition, when the spool 21 is stroked in the left direction from the neutral position as shown in Figs. 7 and 10, the bending plate portion of the movable guide 36 along the inner circumferential surface (flat surface portion 27Al) of the lid 27A. By sliding contact (displacement) 36A, for example, the protruding shaft portion 25 and the movable guide 36 of the spool 21 can be integrally displaced in the lid 27A. It is possible to prevent the movable guide 36 from being discharged from the tip end side of the protruding shaft portion 25 while suppressing the rotation of 25.

For this reason, the dimension L2 of the pilot oil chamber 29A installed in the lid 27A, that is, the length dimension L2 of the flat surface portion 27Al formed on the inner circumferential side of the lid 27A, is expressed by Equation 3 below. As shown in FIG. 10, the length of the protruding shaft portion 25 and the stroke length L can be shortened to a length substantially equal to the total value (see FIG. 10).

[Equation 3]

L2 ≒ L + H

On the other hand, in the comparative example shown in FIG. 11 (an example in which the movable guide is not used), the projecting shaft portion 25 'is formed on the inner circumferential surface of the lid 27A' in order to prevent rotation of the spool 21 (flat surface portion). (27Al ')] in the rotational stop state, the length of the axial length [dimensions H'] of the protrusion shaft portion 25 'exceeding twice the stroke length L (H'> L). It is necessary to form in x 2). In addition, the dimension L2 'of the pilot oil chamber 29A' installed in the cover 27A 'also has a length (L2'> Lx3) exceeding 3 times the stroke length L. There is a need.

As a result, in the comparative example shown in Fig. 11, the cover 27A (the configuration shown in Figs. 8 to 10) in which the length (dimension Lt ') in the axial direction of the lid 27A' is adopted in the present embodiment. It becomes longer by dimension Lt'-Lt than dimension Lt of (), and the total length dimension of the whole apparatus also becomes extra large.

Therefore, in this embodiment, the protruding shaft portion 25 of the spool 21 can be shortened by the size of the movable guide 36 moving in the axial direction (sliding displacement) in the lid 27A. The total length dimension of the direction control valve 11 (spool valve apparatus) shown in 1 can be reliably shortened.

In addition, rotation of the spool 21 in the spool sliding hole 13 of the valve housing 12 can be suppressed by the rotation preventing mechanism 35 made of the movable guide 36, the spring 37, and the like. This can solve the problem of premature wear and damage of the outer circumferential surface of the spool 21 or the spool sliding hole 13. Thereby, also in the direction control valve 11 of the type which stops rotation of the spool 21, the size and weight of the whole apparatus can be realized.

Next, Fig. 12 shows a second embodiment of the present invention, which is characterized in that the spring for holding the movable guide in the state of being inserted into the protruding shaft portion is formed integrally with the same material as the movable guide. have. In addition, in this embodiment, the same code | symbol is attached | subjected to the same component as 1st Embodiment mentioned above, and the description is abbreviate | omitted.

In the figure, reference numeral 41 denotes a rotation prevention mechanism as the rotation stop means employed in the present embodiment, and the rotation prevention mechanism 41 is substantially the same as the rotation prevention mechanism 35 described in the first embodiment. It is comprised by 25A of chamfers, 27A of flat surfaces of cover 27A, the movable guide 42, and the spring 43 mentioned later. However, the rotation prevention mechanism 41 in this case differs in that a plurality of springs 43 are formed integrally with the movable guide 42.

Reference numeral 42 is a movable guide provided between the lid 27A and the protruding shaft portion 25, and the movable guide 42 is configured in substantially the same way as the movable guide 36 described in the first embodiment, and the bending plate portion 42A is provided. And a guide hole 42B, a flat plate-like inner plate portion 42C, and the like. However, the movable guide 42 in this case is different in that the spring 43 mentioned later is integrally formed in the bending plate part 42A.

Reference numerals 43 and 43 are springs constituting the holding member of the rotation preventing mechanism 41, and the springs 43 each move the movable guide 42 similarly to the spring 37 described in the first embodiment. It always presses toward the step surface 26 of and maintains the guide hole 42B of the movable guide 42 in the state which inserted in the protrusion shaft part 25. As shown in FIG.

However, the spring 43 in this case is integrally formed with the movable guide 42, and extends in a zigzag form toward the bottom of the lid 27A from the tip end side of the bent plate portion 42A. Then, the spring 43 has the front end side in contact with the bottom of the lid 27A with a spring property, and elastically presses the end face of the movable guide 42 to the step surface 26 of the spool 21. It is composed.

In this way, also in this embodiment comprised in this way, the effect similar to the said 1st Embodiment can be acquired, and the compactness and weight reduction of the whole apparatus can be achieved. In particular, in this embodiment, since the spring 43 of the rotation prevention mechanism 41 is formed integrally with the movable guide 42, the number of parts can be reduced and the workability at the time of assembly can be improved.

Next, Fig. 13 shows a third embodiment of the present invention, and a feature of the present embodiment is that the holding member for holding the movable guide in the state inserted into the protruding shaft portion is constituted by the fixing member of the movable guide. In addition, in this embodiment, the same code | symbol is attached | subjected to the same component as 1st Embodiment mentioned above, and the description is abbreviate | omitted.

In the figure, reference numeral 51 denotes a rotation prevention mechanism as the rotation stop means employed in the present embodiment, and the rotation prevention mechanism 51 is substantially the same as the rotation prevention mechanism 35 described in the first embodiment, and the protrusion shaft portion ( 25A of chamfers 25, the flat surface part 27Al of the cover 27A, the movable guide 36, etc. are comprised. However, the rotation prevention mechanism 51 in this case differs in that the movable guide 36 is kept in the fall prevention state with respect to the protrusion shaft part 25 by using the fall prevention plate 52 mentioned later as a holding member. .

Reference numeral 52 denotes a release prevention plate constituting the release prevention member of the movable guide 36. The release prevention plate 52 is formed by using a metal plate such as a seat (washer), for example, and the protruding shaft portion 25 Is secured (fastened) to the end surface of the distal end side by using a fastening member such as a bolt 53 or the like. And the fall prevention plate 52 restrict | limits that the outer peripheral side is radiate | emitted from radial direction outward orientation from the protrusion shaft part 25, and that the movable guide 36 is taken out from the front end side of the protrusion shaft part 25 (falling prevention). It is.

Moreover, the bolt 53 as a fastening member is formed with the outer diameter whose head part is smaller than the connection port 28A (hole diameter) of the cover 27A, for example, when the spool 21 is largely stroked to the left direction, the bolt The head portion of the 53 is configured to be inserted (received) with a gap in the connection port 28A.

In this way, also in this embodiment comprised in this way, the effect similar to the said 1st Embodiment can be acquired, and the compactness and weight reduction of the whole apparatus can be achieved. In particular, in the present embodiment, the movable guide 36 can be kept in the preventive state of falling off from the protruding shaft portion 25 by the anti-logging plate 52 which is fixed to the distal end side end surface of the protruding shaft portion 25.

Next, FIG. 14 shows 4th Embodiment of this invention, In this embodiment, the same code | symbol is attached | subjected to the same component as 1st Embodiment mentioned above, and the description is abbreviate | omitted. However, the feature of the present embodiment is that the stop guide 62 is provided on the distal end side of the protruding shaft portion 61 provided on the spool 21, so that the movable guide 36 is prevented from falling out of the protruding shaft portion 61. It is in the structure to hold.

Here, the protruding shaft portion 61 of the spool 21 is configured almost the same as the protruding shaft portion 25 described in the first embodiment, and has chamfered portions 61A and 61A made of flat surfaces. However, in this case, the protruding shaft portion 61 has a small-diameter convex portion 61B at a position that is closer to the tip end side than the chamfered portion 61A, and the stop wheel 62 is detachable on the outer circumferential side of the convex portion 61B. An annular groove 61C is formed to be fitted.

And the stop wheel 62 is comprised, for example by E-type or C-type stop wheel, and is provided so that it may insert in the annular groove 61C of the protrusion shaft part 61 from radial direction outer side. Thereby, the stop wheel 62 comprises the fall prevention member (holding member) which keeps the movable guide 36 in the fall prevention state with respect to the protrusion shaft part 61. As shown in FIG.

In this way, also in this embodiment comprised in this way, the rotation prevention mechanism 63 (rotation stop means) of the spool 21 is made into the flat surface part 27Al of the cover 27A, the movable guide 36, and the protrusion shaft part 61. It can comprise with 61 A of chamfers, 61 C of annular grooves, the stop wheel 62, etc., and the effect similar to the said 1st Embodiment can be acquired.

Next, Fig. 15 shows a fifth embodiment of the present invention. In this embodiment, the same components as those in the above-described first embodiment will be denoted by the same reference numerals and the description thereof will be omitted. However, the feature of this embodiment is that it is set so that the movable guide 72 may be inserted from the radial direction outer side with respect to the protrusion shaft part 71 provided in the spool 21.

Here, the protruding shaft portion 71 of the spool 21 is configured in almost the same way as the protruding shaft portion 25 described in the first embodiment, and has chamfered portions 71A and 71A made of flat surfaces. However, in this case, the protruding shaft portion 71 has the fixing protrusion 71B at a position that is closer to the tip end side than the chamfer 71A. And the fall prevention protrusion 71B of the protrusion shaft part 71 comprises the fall prevention member (holding member) which keeps the movable guide 72 in the fall prevention state with respect to the protrusion shaft part 71. As shown in FIG.

Moreover, the movable guide 72 is comprised substantially similarly to the movable guide 36 described in 1st Embodiment, and has the bending plate part 72A, the guide hole 72B, the inner-plate part 72C of flat surface shape, etc. have. However, the movable guide 72 in this case is different in that the guide hole 72B is formed as a notch hole opened substantially U-shaped at the position of the opening end 72D.

Then, the movable guide 72 is provided to be inserted from the radially outer side with respect to the chamfer 71A of the protruding shaft portion 71, and in this state can move relative to the protruding shaft portion 71 in the axial direction and protrude. Extraction in the axial direction from the shaft portion 71 is regulated by the release preventing protrusion 71B.

Thus, also in this embodiment comprised in this way, the rotation prevention mechanism 73 (rotation stop means) of the spool 21 is made into the flat surface part 27Al of the cover 27A, and the chamfering part 71A of the protrusion shaft part 71. FIG. ), The fall prevention protrusion 71B, the movable guide 72, and the like, and almost the same effect as that of the first embodiment can be obtained.

In addition, in the said 5th Embodiment, the case where the fall prevention protrusion 71B for the movable guide 72 was formed integrally with the protrusion shaft part 71 was demonstrated as an example. However, this invention is not limited to this, For example, the fall prevention protrusion (fall prevention member) for the movable guide 72 is formed separately from a protrusion shaft part, and it uses a means, such as a bolt, a rivet, adhesion | attachment, or welding, for example. It is good also as a structure which integrates (fixes) both.

In addition, in the said 1st Embodiment, the case where the inner board part 36C, 36C which forms a flat surface shape is formed over and below the guide hole 36B of the movable guide 36 was demonstrated as an example. However, this invention is not limited to this, For example, you may make it the structure which provides only a non-circular guide hole in the inner peripheral side of a movable guide, and closes an inner board part etc., for example. In this case as well, the movable guide can be kept in a rotational stop state with respect to the protruding shaft portion. In addition, such a change is possible similarly about 2nd-5th embodiment.

In addition, in each said embodiment, the directional control valve 11 for hydraulic cylinders 5 was demonstrated as an example as a spool valve apparatus. However, the present invention is not limited to this, and may be applied to, for example, a directional control valve such as a hydraulic motor. Moreover, you may apply to spool valve apparatuses, such as a pressure control valve and a flow control valve other than this.

As described above, according to the invention described in claim 1, the rotation stop means for preventing the spool from rotating in the spool sliding hole is located between one cover and the spool to be fitted in the rotation stop state in the cover. Since it is comprised using the movable guide which follows the said spool and moves to an axial direction, when a spool is stroked from a neutral position to one direction (for example, a right direction), for example, the protrusion shaft part provided in the spool is a movable guide. The sliding movement displacement (relative displacement) with respect to the axial direction can be performed, and the rotation of the spool can be stopped by the protruding shaft portion and the movable guide. In addition, when the spool is stroked from the neutral position to the other direction (for example, the left direction), the movable guide is slidably displaced along the inner circumferential surface of the lid, so that, for example, the protruding shaft portion of the spool and the movable guide are integrated in the lid. The shaft can be axially moved (displaced), and the rotation of the spool can be suppressed even at this time.

Therefore, the protruding shaft portion of the spool can be shortened by the size of the movable guide moving in the axial direction (sliding displacement) within the lid, so that the overall length of the spool valve device can be shortened. In addition, the rotation of the spool in the spool sliding hole of the valve housing can be suppressed, thereby eliminating problems such as premature wear and damage of the outer circumferential surface of the spool or the spool sliding hole. As a result, even a spool valve device of the type which stops the rotation of the spool, the device can be reduced in size and weight.

Moreover, according to invention of Claim 2, the spool is provided with the protrusion shaft part which protrudes in the axial direction toward the inside of one cover from the end surface of the one axial direction, and the said movable guide is provided between the said cover and the movable guide. Since the spring which always presses toward the end surface of the structure is provided, the spring can be pressed with the spring so as to elastically press the movable guide against the end surface of the axial side of the spool in which the protruding shaft portion is provided. The inner circumferential side of the movable guide can be kept in a state where it is prevented from being pulled out while being inserted into the protruding shaft portion. And in the state which pressed the movable guide to the end surface of the spool by the spring, the protrusion shaft part of the spool and the movable guide can be displaced integrally, and rotation of a spool can be suppressed.

On the other hand, in the invention according to claim 3, since the movable guide is held in the preventive state of falling off with respect to the protruding shaft portion by the anti-logging provided on the tip end side of the protruding shaft portion, for example, the protruding shaft portion of the spool is provided with the movable guide. Even when it is displaced relative to the direction dispensing from the inner circumferential side, the movable guide can be prevented from being pulled out by the release preventing member, and the movable guide can be kept in the inserted state in the projecting shaft portion.

Further, according to the invention of claim 4, the chamfer portion is provided on the protruding shaft portion of the spool, and the flat surface portion is provided on the inner circumferential side of one cover, so that the inner circumferential side of the movable guide is inserted into the protruding shaft portion. By the chamfer part, it can hold | maintain in a rotation stop state, and the outer peripheral side of a movable guide can be kept in the state which stopped rotation by the flat surface part of the said cover. As a result, the protruding shaft portion of the spool can be kept in the rotation stop state while axially moving (displaced) in the lid via the movable guide, and the rotation of the spool in the spool sliding hole of the valve housing can be suppressed.

Claims (4)

A valve housing provided with a spool sliding hole and a plurality of oil passages communicating with the spool sliding hole, a spool inserted into the spool sliding hole of the valve housing to communicate with and blocking the plurality of oil passages; The left and right lids disposed on both sides of the axial direction of the valve housing to form a pilot oil chamber therein for driving the spool in the axial direction, and provided on either side of the lid of the left and right lids; In the spool valve device comprising a rotation stop means for suppressing rotation in the spool sliding hole, And the rotation stop means is constituted by a movable guide positioned between the one cover and the spool, fitted in the rotation stop state in the cover, and movable in the axial direction following the spool. The said spool is provided with the protrusion shaft part which protrudes in the axial direction from the end surface of the one side of an axial direction toward the said cover, and the said movable guide is inserted in rotation stop state, The said cover and the movable guide are provided. And a spring for urging the movable guide toward the end face of the spool at all times and for maintaining the movable guide in a fall prevention state. The said spool is provided with the protrusion shaft part which protrudes axially from the end surface of the one side of an axial direction toward the said one cover, and the said movable guide is inserted in rotation stop state, The tip part of the said projection shaft part is provided. The spool valve apparatus provided in the side by providing the fall prevention member which keeps the said movable guide in a fall prevention state. According to claim 2 or 3, Protruding shaft portion of the spool is provided with a flat chamfer extending in parallel in the axial direction, One side cover is provided with a flat surface portion on the inner peripheral side where the pilot oil chamber is formed, And the movable guide is configured to be held in a rotational stop state by the chamfer portion of the protruding shaft portion and the flat surface portion of the lid.

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