JP2009014037A - Control valve for working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance flexibility of arrangement of a selector valve and to easily install an additional attachment valve. <P>SOLUTION: On a high-pressure port face 36 of a control valve body 32 to which an option valve for controlling operation of two types of option hydraulic actuators selectively provided is incorporated, the selector valve 42 for switching a flow passage of return oil in accordance with the option actuator to be selected is mounted. The selector valve 42 is constituted as a manual operation-type rotary valve for performing a flow passage switching action by rotation of a rotary shaft by lever operation, and a lever is mounted in a dropped state to the rotary shaft. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control valve used in a work machine to which two types of work devices (for example, an open / close-type crusher and a breaker) are selectively attached like a crusher.

  For example, a crusher for crushing a building or the like is equipped with a work attachment on a crawler traveling base machine, and an open / close type crusher called a nibra is attached to the tip of the work attachment according to the content of the work. Or vibration breaker as an option. Hereinafter, the work by the crusher is called crushing work, and the work by the breaker is called breaker work.

  In this case, the crusher and breaker use different types of hydraulic actuators (optional hydraulic actuators) as the drive source, and the route of return oil from both actuators must be different, so the circuit state depends on the work device to be installed. Need to be switched.

  FIG. 6 shows the configuration of a hydraulic circuit having this switching function.

  The crusher is provided with a left and right traveling motor, a swing motor, a boom cylinder for raising and lowering the boom, and a plurality of hydraulic actuators as standard actuators. Each standard actuator is individually controlled by the valve body 2 of the control valve 1. A plurality of actuator control valves (spool holes and spools, not shown), a pump line 4 connected to the pump 3, and a tank line 5 connected to the tank T are provided.

  The tank line 5 is branched on the downstream side into a main tank line 6 and a bypass tank line 8 having a bypass relief valve 7 for protecting the oil cooler. The main tank line 6 is connected to the tank T via the oil cooler 9. The bypass tank lines 8 are directly connected to the tanks T, respectively.

  An optional valve 10 (spool hole and spool) shared by the optional actuator is provided on the downstream side of the pump line 4 in the valve body 2.

  This optional valve 10 is operated by a pedal-type remote control valve (not shown), and by operating this optional valve 10, oil from the hydraulic pump 3 is crushed by pressure oil supply lines 11 and 12 provided in the valve body 2. These are sent to the crushing cylinder 13 which is the drive source of the apparatus or the breaker cylinder 14 which is the drive source of the breaker to operate them.

  Here, at the time of the crushing operation, the crushing cylinder 13 is connected to the hydraulic pump 3 and the tank T through a normal route via the option valve 10 as in a general double-action cylinder circuit.

  On the other hand, if the back pressure of the bypass relief valve 7 or the back pressure of the option valve 10 is raised during the breaker operation, the breaker force becomes weak and the operation becomes worst. Further, since the oil cooler 9 is pulsated, the oil cooler 9 may be damaged.

  Therefore, a selector valve 15 is provided on the outer surface of the valve body 2, and when the breaker is operated, the return line 16 for the optional actuator is directly connected to the tank T through the return pipe 17 dedicated for the breaker by switching the selector valve 15. It is comprised so that.

  The selector valve 15 is configured as a manually operated rotary valve in which the rotary shaft 18 rotates by operation of a lever (not shown), and a channel switching action is performed by a T-shaped internal passage 19 provided in the rotary shaft 18.

  FIG. 6 shows the position of the selector valve 15 during the crushing operation, and the internal passage 19 communicates with the return line 16 and the pressure oil supply line 12 at this crushing operation position. Accordingly, both the side lines of the crushing cylinder 13 are connected to the hydraulic pump 3 and the tank T via the option valve 10.

  On the other hand, at the time of the breaker work, the selector valve 15 is rotated 90 ° to be switched to the breaker work position, and the internal passage 19 communicates with the return line 16 and the return pipe 17 at this breaker work position. Accordingly, the return oil from the breaker cylinder 14 is returned directly to the tank T without passing through the option valve 10 and the tank line 5.

  As described above, Patent Document 1 discloses a technique for switching the flow path of the actuator return oil according to the type of the work device by the selector valve 15.

  The selector valve 15 is configured as a pasted valve different from the valve body 2 and is added on to the valve body 2.

  In this case, in the conventional control valve 1, as shown in FIGS. 6 to 8, the selector valve 15 is attached to the end of the valve body 2, that is, the end face 20 on the most downstream side when viewed from the pump side (Patent Document). 2).

  7 and 8, the valve body 2 includes an actuator control valve for each actuator, that is, a spool hole 21, a spool 22 that operates in a stroke in the spool hole 21, and oil in the spool hole 21. .. To the outside are provided at intervals in one direction (in the direction of the pump line 4 in FIG. 6 and in the vertical direction in FIGS. 7 and 8). Actuator ports 25, which are pipe connection ports of the passages 23, are provided.

Further, a spool hole 26 and a spool 27 for the option valve 10 in FIG. 6 are provided on the most downstream side of the valve body 2, and a selector valve 15 is attached to the end surface 20 on the most downstream side. The optional valve spool hole 26 is connected via a selector valve passage 28 and the port 29.
JP 2002-294758 A Japanese Patent Laid-Open No. 2004-324741

  However, according to the known technique in which the selector valve 15 is attached to the end surface 20 on the most downstream side of the valve body 2 as described above, the following problem has occurred.

  (I) In order to reduce the pressure loss due to the selector valve passage 28 as much as possible, the optional valve 10 (the optional valve spool hole 26 and the spool 27 in FIG. 8) is connected to the selector valve 15 as shown in FIG. 2 must be provided on the most downstream side.

  That is, the position of the option valve 10 in the valve body 2 is limited, and the degree of freedom in design is low.

  (Ii) By attaching the selector valve 15 to the end face 20 on the most downstream side, it is difficult to add another sticking valve to the end face 20.

  In particular, if a manually operated rotary valve that is advantageous in that the pressure loss is small as compared with the spool valve as described above is used as the selector valve 15, it is necessary to secure an operation space. Has become extremely difficult.

  Accordingly, the present invention provides a control valve for a work machine in which a selector valve mounting position with respect to a valve body can be freely selected, and another sticking valve can be easily added.

  The invention of claim 1 comprises a valve body in which a plurality of actuator control valves for controlling the operation of a plurality of hydraulic actuators are incorporated at intervals in one direction, and is optionally attached to a machine as an option. An optional valve is installed as a common valve that controls the operation of two types of optional hydraulic actuators, and a selector valve that switches the return oil flow path according to the selected optional actuator is attached to the outer surface of the main body. In the control valve of the work machine, the selector valve is configured as a manually operated rotary valve that performs a flow path switching operation by rotating the rotary shaft by lever operation, and the selector valve is configured by each hydraulic actuator in the valve body. One actuator port The rotary shaft is mounted on the high-pressure port surface arranged in parallel with a distance in the direction in which the rotary shaft is parallel to the actuator port arrangement direction and the tip protrudes in the actuator port arrangement direction. A lever is attached to the tip.

  According to a second aspect of the present invention, in the configuration of the first aspect, a lever fitting groove is provided on the tip surface of the rotary shaft, and the lever is attached to the tip of the rotary shaft in a state of being fitted in the lever fitting groove. It is.

  According to the present invention, since the selector valve is attached to the high-pressure port surface of the valve body, the attachment position of the selector valve can be set to an arbitrary position in the direction in which the actuator ports are arranged.

  Therefore, the position of the option valve is not limited to the most downstream side, and can be freely selected in consideration of the positional relationship with other spools, the connection of piping, and the like, so that the degree of freedom in design can be increased.

  Further, since the end face on the most downstream side of the valve body is vacant, another sticking valve can be easily added to the end face.

  Furthermore, since a manually operated rotary valve is employed as the selector valve, the pressure loss can be reduced as compared with the spool valve.

  By the way, according to the present invention in which a selector valve (manually operated rotary valve) is attached to a high pressure port surface provided with another actuator port, the valve may interfere with piping connection to an adjacent actuator port. . For this reason, it is necessary to make the whole valve thickness including the lever for operation as small as possible.

  In this respect, according to the invention of claim 2, a lever fitting groove is provided on the tip surface of the rotary shaft, and the lever is attached to the tip of the rotary shaft in a state of being fitted (dropped) into the lever fitting groove. The valve thickness dimension including the lever can be suppressed, and the piping connection space of the adjacent port can be secured.

  An embodiment of the present invention will be described with reference to FIGS.

  1 and 2 show a control valve 31 according to the embodiment.

  The basic structure of the main body 32 of the control valve 31 is the same as that of the main body 2 of the known control valve 1 shown in FIGS.

  That is, a spool hole 33 for actuator control valve, a spool 34 that operates in a stroke in the spool hole 33, and a passage 35 that guides oil to the outside from the spool hole 21 are provided in one direction in the valve body 32. (In the direction of the pump line 4 in FIG. 6; hereinafter referred to as the vertical direction in accordance with the directionality in both figures) and spaced from each other, and at the pipe connection port of each passage 35. A certain actuator port 37 is provided.

  Further, the optional valve spool hole 38 and the spool 39, and the selector valve extending from the spool hole 38 toward the high-pressure port surface 36 at an arbitrary position in the vertical direction of the valve body 32 (downstream position in the illustrated example). A passage 40 and a port 41 are provided, and a selector valve 42 is attached to the high-pressure port surface 36 (selector valve port 41) at the same vertical position as these.

  Therefore, in the case of this control valve 31, an end cover or another sticking valve is attached to the end face (endmost end face) 43 of the valve body 32.

  The configuration of the selector valve 42 will be described with reference to FIG.

  The selector valve 42 is configured as a manually operated rotary valve in which the rotary shaft 45 rotates around its axis by the operation of the lever 44. The rotary shaft 45 is parallel to the direction in which the actuator ports 37. It is attached to the high-pressure port surface 36 with its tip protruding in the port alignment direction.

  The rotary shaft 45 is provided with a T-shaped internal passage 46. Similar to the selector valve 15 shown in FIG. 6, the rotary shaft 45 is rotated according to the crushing operation and the breaker operation, whereby the internal passage 46 is formed. The flow path switching action is performed by rotating between two positions (crushing operation position and breaker operation position) at intervals of approximately 90 °.

  5, 47 is a return passage connected to the return line 16 in FIG. 6, FIGS. 3 and 5, 48 is the same port, and in FIG. 4, 49 is a tank passage connected to the return pipe 17 in FIG. , 50 are the same ports.

  Thus, in order to attach the selector valve 42 to the high-pressure port surface 36 of the control valve main body 32, the attachment position of the selector valve 42 can be set to an arbitrary position in the vertical direction (alignment direction of the actuator ports 37). it can.

  Therefore, the position of the option valve (spool hole 38 and spool 39) is not limited to the most downstream side as in the prior art, but can be freely selected in consideration of the positional relationship with other spools, the piping relationship, and the like. Therefore, the degree of freedom in design can be increased.

  Further, since the end face 43 on the most downstream side of the control valve main body 32 is vacant, another sticking valve can be easily added to the end face 43.

  Further, since a manually operated rotary valve is employed as the selector valve 42, the pressure loss can be reduced as compared with the spool valve.

  By the way, if the selector valve 42 is attached to the high pressure port surface 36 along with the other actuator ports 37 as described above, the valve 42 may interfere with the piping connection to the adjacent actuator port. FIG. 2 shows a situation where there are other actuator ports 37, 37 on the upper and lower sides of the selector valve 42, and pipes 51, 52 are connected to both actuator ports 37, 37.

  Therefore, the entire valve thickness dimension S including the lever 44 (shown in FIG. 2) needs to be as small as possible, and thus the following configuration is adopted.

  A head 45a having a diameter larger than that of the shaft main body is provided at the upper end of the rotary shaft 45, and a lever fitting groove 53 extending in the diameter direction is provided at the center of the upper surface of the head 45a.

  The lever 44 is attached to the shaft head 45a by screws 54, 54 in a state where about half of the thickness of the lever 44 is fitted in the lever fitting groove 53.

  A set screw 55 is screwed into the middle portion of the lever 44 in the length direction, and both fixing and crushing holes 56 and 57 for crushing work and breaker work are provided on the upper surface of the selector valve 42 to perform both crushing and breaker work. The set screw 55 is screwed in at the position, and the through end portion thereof is fitted into the fixing holes 56 and 57. Thereby, the lever 44 (rotary shaft 45) is fixed to both positions.

  With this configuration, the valve thickness dimension S including the lever 44 can be kept small, and a pipe connection space between the adjacent ports 37 and 37 can be secured.

  In order to further reduce the bulb thickness dimension S, the head of the set screw 55 may be dropped into a recess provided on the upper surface of the bulb. Alternatively, instead of the set screw 55, a configuration may be adopted in which a leaf spring is attached to the lower surface of the lever 44, and a protrusion provided on the leaf spring is elastically engaged with the fixing holes 56 and 57 to fix the lever 44 in two positions. .

  By the way, when the valve thickness can be reduced to the same level as the above embodiment without adopting the lever mounting structure as described above, the lever 44 can be directly attached to the tip surface (head 45a) of the rotary shaft 45. Good.

  Moreover, although the case where the whole control valve 31 was installed vertically long (up-down direction) was illustrated in the said embodiment, when this is installed horizontally, it can implement similarly to the above.

It is a perspective view of the control valve concerning the embodiment of the present invention. It is sectional drawing of the same valve. It is a perspective view of the selector valve which comprises a control valve. FIG. It is the same top view. It is a figure which shows the installation condition and hydraulic circuit structure of the conventional control valve. It is a perspective view of the conventional control valve. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 13 Crushing cylinder 14 Breaker cylinder 31 Control valve 32 Control valve main body 33 Spool hole of actuator control valve 34 Spool of actuator control valve 35 Passage for actuator control valve 36 High pressure port surface of valve main body 37 Actuator port 38 Spool hole of optional valve 39 Same spool 40 Selector valve passage 41 Selector valve port 42 Selector valve 44 Selector valve lever 45 Same rotary shaft 45a Shaft head 46 Internal passage 53 Lever fitting groove

Claims (2)

  Two types of optional hydraulic actuators that have a valve body with multiple actuator control valves that control the operation of multiple hydraulic actuators, spaced in one direction, and can be selectively mounted on the machine as an option In a control valve for a work machine in which an optional valve as a common valve for controlling the operation of the engine is incorporated and a selector valve for switching a return oil flow path according to an optional actuator selected is attached to the outer surface of the main body. The selector valve is configured as a manually operated rotary valve in which the rotary shaft rotates by lever operation to switch the flow path, and the selector valve is spaced in one direction between the actuator ports of the hydraulic actuators in the valve body. Put The rotary shaft is mounted on the installed high-pressure port surface in a state where the rotary shaft is parallel to the actuator port alignment direction and its tip protrudes in the actuator port alignment direction, and a lever is mounted on the rotary shaft tip. A control valve for work machines.   2. A control valve for a work machine according to claim 1, wherein a lever fitting groove is provided on a tip surface of the rotary shaft, and the lever is attached to the tip of the rotary shaft in a state of being fitted in the lever fitting groove. .

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