Control valve and rice transplanter

Abstract

The present application relates to a control valve and a rice transplanter. The control valve includes a valve body and a valve stem. The valve body is provided with a valve cavity, a main oil inlet channel, a first oil distribution channel, a second oil distribution channel, a first oil return channel, a second oil return channel and a first oil outlet channel. The valve stem is movably arranged in the valve cavity. When the valve stem controls the main oil inlet channel to connect to the first oil distribution channel, the second oil distribution channel connects to the second oil return channel. When the valve stem controls the main oil inlet channel to connect to the second oil distribution channel, the first oil distribution channel connects to the first oil return channel. The control valve is equipped with a pressure limiting valve. When the hydraulic value of the pressure oil in the main oil inlet channel is greater than the preset pressure value, the pressure limiting valve opens the first oil outlet channel to connect the main oil inlet channel and the first oil return channel. The control valve and rice transplanter provided by the present application solve the problem that when the amount of pressure oil entering the main oil inlet channel of the existing control valve is too large, it is easy to cause irreversible damage to the control valve.

Description

Technical Field

[0001] The present application relates to the technical field of agricultural machinery, and in particular to a control valve and a rice transplanter. Background Art

[0002] Usually, the control valve includes a valve body and a valve stem, and the valve body is provided with a valve cavity, a main oil inlet channel, a first oil distribution channel, a second oil distribution channel, a first oil return channel and a second oil return channel. The valve stem is located in the valve cavity to control the opening and closing of the valve cavity and the first oil distribution channel, the second oil distribution channel, the first oil return channel and the second oil return channel respectively. However, when the amount of pressurized oil entering the main oil inlet channel is too large, it is easy to cause irreversible damage to the control valve. Summary of the invention

[0003] Based on this, it is necessary to provide a control valve and a rice transplanter to solve the problem that when the amount of pressurized oil entering the main oil inlet channel of the existing control valve is too large, it is easy to cause irreversible damage to the control valve.

[0004] The control valve provided in the present application includes a valve body and a valve stem. The valve body is provided with a valve cavity, a main oil inlet channel, a first oil distribution channel, a second oil distribution channel, a first oil return channel, a second oil return channel and a first oil outlet channel. The main oil inlet channel is connected to the first oil distribution channel and the second oil distribution channel through the valve cavity, the first oil return channel is connected to the first oil distribution channel through the valve cavity, the second oil return channel is connected to the second oil distribution channel through the valve cavity, and the main oil inlet channel is connected to the first oil return channel through the first oil outlet channel. The valve stem is movably arranged in the valve cavity. When the valve stem controls the main oil inlet channel to be connected to the first oil distribution channel, the second oil distribution channel is connected to the second oil return channel. When the valve stem controls the main oil inlet channel to be connected to the second oil distribution channel, the first oil distribution channel is connected to the first oil return channel. The control valve is equipped with a pressure limiting valve. When the hydraulic value of the pressure oil in the main oil inlet channel is greater than the preset pressure value, the pressure limiting valve opens the first oil outlet channel to connect the main oil inlet channel and the first oil return channel.

[0005] In one embodiment, the pressure limiting valve includes a second movable plug and a second resetting elastic member connected to one end of the second movable plug, and the second resetting elastic member can push the second movable plug to block the first oil outlet channel. It can be understood that such a configuration is conducive to reducing the processing difficulty of the pressure limiting valve.

[0006] In one embodiment, a guide seat is provided on the side of the first oil outlet passage close to the second movable plug, and the guide seat is provided with a guide hole connected to the first oil outlet passage. The second movable plug includes a conical head and a main body fixed to the end of the head away from the guide seat, and the head, the main body, the second movable plug and the guide hole are coaxially arranged. When the second movable plug blocks the first oil outlet passage, the second movable plug part of the head is inserted into the guide hole; the outer diameter of the main body is greater than the maximum outer diameter of the head, and the end face of the main body close to the head is provided with a circle of annular jet grooves around the head, and the opening of the jet grooves faces the head. It can be understood that such a setting is conducive to improving the matching accuracy of the second movable plug and the first oil outlet passage, and preventing the second movable plug from being eccentric, which causes abnormal noise of the pressure limiting valve during operation.

[0007] In one embodiment, the guide seat is provided with a circle of annular bevels, and the annular bevels are provided at the opening of the guide hole close to one end of the second movable plug. It can be understood that such a configuration is conducive to the second movable plug being inserted into the guide hole.

[0008] In one embodiment, the hardness of the guide seat is greater than the hardness of the valve body; and / or the guide seat is made of medium carbon steel. It is understandable that, with such a configuration, the guide seat is unlikely to deform under the impact of the second movable plug, effectively ensuring the sealing of the pressure limiting valve.

[0009] In one embodiment, the guide seat is welded to the valve body, or the guide seat is clamped to the valve body. It can be understood that such a configuration is conducive to improving the firmness of the connection between the guide seat and the valve body.

[0010] In one embodiment, the valve body is provided with a mounting flare, which is provided at one end of the first oil outlet passage close to the second movable plug, and the inner diameter of the mounting flare is larger than the inner diameter of the first oil outlet passage, the guide seat is provided at the mounting flare, the inner diameter of the guide hole is equal to the inner diameter of the first oil outlet passage, and the guide hole is provided coaxially with the first oil outlet passage. It can be understood that such a setting is conducive to the smooth flow of pressurized oil from the first oil outlet passage to the guide hole.

[0011] In one embodiment, a stop flange is provided at one end of the guide seat close to the second movable plug, and the stop flange stops at the edge of the installation expansion opening close to the second movable plug. It can be understood that such a setting is conducive to improving the installation convenience of the guide seat.

[0012] In one embodiment, the control valve further includes a first return elastic member, the first return elastic member is connected to one end of the valve stem, and one end of the valve stem connected to the first return elastic member extends out of the valve cavity.

[0013] The present application also provides a rice transplanter, which includes the control valve described in any one of the above embodiments.

[0014] Compared with the prior art, the control valve and rice transplanter provided by the present application, when the hydraulic pressure value of the pressure oil in the main oil inlet channel is greater than the preset pressure value, the pressure oil in the main oil inlet channel can enter the first oil return channel through the first oil outlet channel for oil return, so as to reduce the hydraulic pressure in the main oil inlet channel, and when the hydraulic pressure in the main oil inlet channel is less than the preset pressure value, the pressure limiting valve closes the first oil outlet channel. That is, by providing the first oil outlet channel and the pressure limiting valve, the hydraulic pressure of the pressure oil in the main oil inlet channel can be controlled within a range not exceeding the preset pressure value, so as to avoid damage to the control valve due to excessive pressure in the control valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 A cross-sectional view of a control valve provided for this application;

[0017] Figure 2 A cross-sectional view of the guide seat provided for this application;

[0018] Figure 3 Piping diagram of the control valve provided for this application.

[0019] Reference numerals: 100, valve body; 110, valve chamber; 111, first sealing ring; 112, second sealing ring; 120, main oil inlet channel; 130, first oil distribution channel; 140, second oil distribution channel; 150, first oil return channel; 160, second oil return channel; 170, first oil outlet channel; 180, installation flare; 190, second oil outlet channel; 200, valve stem; 210, connecting groove; 300, operating lever; 400, first reset spring Part; 500, mounting cap; 510, assembly cavity; 520, mounting flange; 530, guide cavity; 600, pressure limiting valve; 610, second movable plug; 611, sealing head; 612, guide rod; 613, head; 614, main body; 615, jet groove; 620, second reset elastic member; 630, mounting seat; 700, guide seat; 710, guide hole; 720, annular slope; 730, stop flange; 800, unloading valve. DETAILED DESCRIPTION

[0020] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0021] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0022] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0023] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0024] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0026] See also Figure 1 and Figure 3 The control valve provided in the present application includes a valve body 100 and a valve stem 200. The valve body 100 is provided with a valve cavity 110, a main oil inlet channel 120, a first oil distribution channel 130, a second oil distribution channel 140, a first oil return channel 150 and a second oil return channel 160. The main oil inlet channel 120 is connected to the first oil distribution channel 130 and the second oil distribution channel 140 through the valve cavity 110, the first oil return channel 150 is connected to the first oil distribution channel 130 through the valve cavity 110, and the second oil return channel 160 is connected to the second oil distribution channel 140 through the valve cavity 110.

[0027] The valve stem 200 is movably disposed in the valve chamber 110. When the valve stem 200 controls the main oil inlet channel 120 to connect to the first oil distribution channel 130, the second oil distribution channel 140 is connected to the second oil return channel 160. When the valve stem 200 controls the main oil inlet channel 120 to connect to the second oil distribution channel 140, the first oil distribution channel 130 is connected to the first oil return channel 150. Specifically, the valve stem 200 is provided with a plurality of connecting grooves 210. When the control valve controls the rice transplanter to rise, the valve stem 200 is pushed to one side by the joystick 300, and the connecting grooves 210 on the valve stem 200 connect the main oil inlet channel 120 and the first oil distribution channel 130, and the second oil distribution channel 140 is also connected to the second oil return channel 160 through the connecting grooves 210 on the valve stem 200. At this time, the pressure oil enters the first oil distribution channel 130 from the main oil inlet channel 120 through the connecting grooves 210, and the pressure oil enters the second oil return channel 160 through the second oil distribution channel 140 to complete the oil return. Similarly, when the control valve controls the rice transplanter to descend, the valve stem 200 is pushed to move to the other side by the joystick 300, and the connecting groove 210 on the valve stem 200 connects the main oil inlet channel 120 and the second oil distribution channel 140, the first oil distribution channel 130 is also connected to the first oil return channel 150 through the connecting groove 210 on the valve stem 200. At this time, the pressure oil enters the second oil distribution channel 140 from the main oil inlet channel 120 through the connecting groove 210, and the pressure oil enters the first oil return channel 150 through the first oil distribution channel 130 to complete the oil return.

[0028] Usually, the staff controls the movement of the valve stem 200 in the valve cavity 110 through the joystick 300 provided on one side of the valve stem 200, and in order to quickly reset the valve stem 200, a first reset elastic member 400 is provided on the side of the valve stem 200 away from the joystick 300, and the first reset elastic member 400 can push the valve stem 200 to move in the direction close to the joystick 300. However, during the movement of the valve stem 200 in the valve cavity 110, the end face of the valve stem 200 connected to the first reset elastic member 400 will be subjected to the pressure from the pressure oil in the valve cavity 110, so that the joystick 300 will be subjected to the resistance from the pressure oil in the process of pushing the valve stem 200 to move, thereby increasing the difficulty of the staff to operate the joystick 300 and affecting the staff's operating feel. In order to solve the problem of difficulty in moving the valve stem 200, a solution of using a first reset elastic member 400 with a lower elastic coefficient is usually adopted to reduce the difficulty of moving the valve stem 200. However, lowering the elastic coefficient of the first reset elastic member 400 will cause the reset ability of the valve stem 200 to decrease, resulting in the valve stem 200 being unable to reset in time, affecting the response sensitivity of the control valve.

[0029] See also Figure 1In order to solve the problem of the difficulty in moving the valve stem 200 and not reduce the reaction sensitivity of the control valve, the valve stem 200 of the control valve provided by the present application is connected to the first reset elastic member 400 and one end thereof extends out of the valve cavity 110. In this way, the end surface of the valve stem 200 connected to the first reset elastic member 400 will not be subjected to the pressure from the pressure oil in the valve cavity 110, and the operating rod 300 will not be subjected to the resistance from the pressure oil in the process of pushing the valve stem 200 to move, thereby reducing the difficulty of the staff in operating the operating rod 300 and not affecting the staff's operating feel.

[0030] In order to reduce the difficulty of installing the first resetting elastic member 400, in one embodiment, as Figure 1 As shown, the control valve further includes a mounting cap 500, which is detachably connected to the valve body 100, and is provided with an assembly cavity 510 communicating with the valve cavity 110, one end of the valve stem 200 extends into the assembly cavity 510, and the first return elastic member 400 is provided in the assembly cavity 510, and one end of the first return elastic member 400 is connected to the inner wall of the assembly cavity 510, and the other end is connected to the valve stem 200. In this way, the first return elastic member 400 is first installed in the assembly cavity 510, and then the mounting cap 500 equipped with the first return elastic member 400 is detachably connected to the valve body 100, and one end of the first return elastic member 400 abuts against the valve stem 200, so as to apply a force to the valve stem 200 away from the mounting cap 500. Specifically, in order to facilitate the connection of the mounting cap 500 to the valve body 100 , in one embodiment, a mounting flange 520 is provided at one end of the mounting cap 500 close to the valve body 100 , and the mounting flange 520 is detachably connected to the valve body 100 via fasteners.

[0031] Furthermore, in order to reduce the manufacturing difficulty of the control valve, in one embodiment, as Figure 1 As shown, the first resetting elastic member 400 is a compression spring, but not limited thereto, the first resetting elastic member 400 may also be other elastic members such as a spring sheet, which are not listed here one by one.

[0032] In order to prevent the end of the valve stem 200 connected to the first return elastic member 400 from retracting into the valve cavity 110, in one embodiment, as Figure 1 As shown, the compression spring is coaxially arranged with the valve stem 200, and the maximum extension length of the compression spring along the axial direction of the valve stem 200 is less than the length of the assembly cavity 510 along the axial direction of the valve stem 200. In this way, even if the compression spring reaches the maximum extension length, the compression spring will not extend out of the assembly cavity 510, and will not push the valve stem 200 into the valve cavity 110, which is conducive to the end of the valve stem 200 close to the first return spring always being kept outside the valve cavity 110.

[0033] In order to prevent the compression spring from being eccentric during the expansion and contraction process, in one embodiment, as Figure 1 As shown, a guide cavity 530 communicating with the assembly cavity 510 is provided at one end of the mounting cap 500 away from the valve body 100, the inner diameter of the guide cavity 530 is smaller than the inner diameter of the assembly cavity 510, and one end of the compression spring is inserted into the guide cavity 530 and matches with the inner wall clearance of the guide cavity 530. Further, the guide cavity 530 is firstly machined on the mounting cap 500, and then the inner diameter of the guide cavity 530 is partially enlarged to machine the assembly cavity 510.

[0034] In order to improve the sealing performance of the control valve, in one embodiment, as Figure 1 As shown, a first sealing ring 111 is provided at one end of the valve cavity 110 close to the mounting cap 500, the inner side of the first sealing ring 111 can be movably sleeved on the valve stem 200, and the outer side of the first sealing ring 111 is fixedly arranged on the inner wall of the valve cavity 110. In this way, the pressure oil can be prevented from leaking from between the valve stem 200 and the inner wall of the valve cavity 110, thereby greatly improving the sealing performance of the control valve. The first sealing ring 111 can be a rubber ring, or a silicone ring, etc., which are not listed here one by one.

[0035] In one embodiment, if Figure 1 As shown, the operating rod 300 is connected to one end of the valve stem 200 away from the first reset elastic member 400, and one end of the valve stem 200 connected to the operating rod 300 extends out of the valve cavity 110. In this way, the end surface of one side of the valve stem 200 connected to the operating rod 300 will not be subjected to the pressure from the pressure oil in the valve cavity 110, and in this way, the operating rod 300 will not be subjected to the resistance from the pressure oil in the process of pushing the valve stem 200 to move, thereby reducing the difficulty of the staff to operate the operating rod 300, and will not affect the staff's operating feel. In addition, one end of the valve stem 200 connected to the operating rod 300 extends out of the valve cavity 110, which is conducive to the assembly of the valve stem 200 and the operating rod 300.

[0036] Similarly, in order to improve the sealing performance of the control valve, in one embodiment, as Figure 1 As shown, a second sealing ring 112 is provided at one end of the valve cavity 110 close to the operating rod 300 . The inner side of the second sealing ring 112 can be movably sleeved on the valve stem 200 , and the outer side of the second sealing ring 112 is fixedly arranged on the inner wall of the valve cavity 110 .

[0037] In order to improve the safety of the control valve, in one embodiment, as Figure 1As shown, the valve body 100 is further provided with a first oil outlet channel 170, and the main oil inlet channel 120 is connected to the first oil return channel 150 through the first oil outlet channel 170, and the control valve is equipped with a pressure limiting valve 600. Usually, the pressure limiting valve 600 closes the first oil outlet channel 170. When the hydraulic pressure value of the pressure oil in the main oil inlet channel 120 is greater than the preset pressure value, the pressure limiting valve 600 opens the first oil outlet channel 170 to connect the main oil inlet channel 120 and the first oil return channel 150. In this way, when the hydraulic pressure value of the pressure oil in the main oil inlet channel 120 is greater than the preset pressure value, the pressure oil in the main oil inlet channel 120 can enter the first oil return channel 150 through the first oil outlet channel 170 for oil return, so as to reduce the hydraulic pressure in the main oil inlet channel 120. When the hydraulic pressure in the main oil inlet channel 120 is less than the preset pressure value, the pressure limiting valve 600 closes the first oil outlet channel 170. That is, by providing the first oil outlet channel 170 and the pressure limiting valve 600, the hydraulic pressure of the pressurized oil in the main oil inlet channel 120 can be controlled within a range not exceeding a preset pressure value, thereby avoiding damage to the control valve due to excessive pressure in the control valve.

[0038] Specifically, in order to reduce the difficulty of processing the pressure limiting valve 600, in one embodiment, as Figure 1 As shown, the pressure limiting valve 600 includes a second movable plug 610 and a second reset elastic member 620 connected to one end of the second movable plug 610, and the second reset elastic member 620 can push the second movable plug 610 to block the first oil outlet channel 170. Further, the pressure limiting valve 600 includes a mounting seat 630, which is detachably connected to the valve body 100, and the second movable plug 610 includes a sealing head 611 and a guide rod 612 connected to the sealing head 611, and the second reset elastic member 620 is sleeved on the outer side of the guide rod 612, and one end of the second reset elastic member 620 abuts against the mounting seat 630, and the other end abuts against the sealing head 611, and the second reset elastic member 620 slides with the outer side of the guide rod 612 during the telescopic process to push the second movable plug 610 to block the first oil outlet channel 170.

[0039] In order to improve the matching accuracy between the second movable plug 610 and the first oil outlet channel 170 and prevent the second movable plug 610 from being eccentric and causing abnormal noise in the operation of the pressure limiting valve 600, in one embodiment, Figure 1 and Figure 2As shown, a guide seat 700 is provided on one side of the first oil outlet channel 170 close to the second movable plug 610, and the guide seat 700 is provided with a guide hole 710 connected to the first oil outlet channel 170. The second movable plug 610 includes a conical head 613 and a main body 614 fixed to the end of the head 613 away from the guide seat 700 and is conical, and the head 613, the main body 614, the second movable plug 610 and the guide hole 710 are coaxially arranged. When the second movable plug 610 blocks the first oil outlet channel 170, the head 613 of the second movable plug 610 is partially inserted into the guide hole 710. Specifically, the sealing head 611 is conical as a whole. In this way, the second movable plug 610 is partially inserted into the guide hole 710 under the guiding effect of the guide hole 710, and the inner wall of the guide hole 710 has a certain limiting effect on the second movable plug 610, which can prevent the second movable plug 610 from being eccentric. Furthermore, the outer diameter of the main body 614 is larger than the maximum outer diameter of the head 613, and a circle of annular jet grooves 615 are provided around the head 613 on one side end surface of the main body 614 close to the head 613, and the opening of the jet grooves 615 faces the head 613. The annular jet grooves 615 increase the contact area between the second active plug 610 and the pressure oil, and under the same pressure, the pressure of the pressure oil on the second active plug 610 increases, and the annular jet grooves 615 can reflect part of the pressure oil, so that the second active plug 610 can be opened with a hydraulic pressure less than 10 MPA instead of the original 10 MPA hydraulic pressure, that is, the opening and closing characteristics of the pressure limiting valve 600 are improved.

[0040] In order to facilitate the insertion of the second movable plug 610 into the guide hole 710, in one embodiment, as Figure 1 and Figure 2 As shown, the guide seat 700 is provided with a circle of annular bevels 720, and the annular bevels 720 are provided at the opening of the guide hole 710 close to one end of the second movable plug 610. In this way, it is more conducive for the second movable plug 610 to slide into the guide hole 710 along the annular bevels 720, thereby improving the fault tolerance rate of the pressure limiting valve 600.

[0041] Generally, the valve body 100 is formed by casting, and the hardness of the cast valve body 100 is relatively low. Under the repeated impact of the second movable plug 610, the valve body 100 is easily deformed, which leads to leakage of the pressure limiting valve 600. In order to prevent the valve body 100 from deforming under the impact of the second movable plug 610, in one embodiment, the hardness of the guide seat 700 is greater than the hardness of the valve body 100. In this way, the second movable plug 610 directly impacts the guide seat 700, and the contact area between the guide seat 700 and the valve body 100 is much larger than the original contact area between the second movable plug 610 and the valve body 100. In this way, the pressure on the valve body 100 by the second movable plug 610 is effectively reduced, and the probability of deformation of the valve body 100 is greatly reduced. Furthermore, since the hardness of the guide seat 700 is greater than that of the valve body 100, the guide seat 700 is unlikely to deform under the impact of the second movable plug 610, thereby effectively ensuring the sealing of the pressure limiting valve 600. Furthermore, the guide seat 700 is made of medium carbon steel, which has high hardness and certain toughness.

[0042] In order to improve the connection firmness between the guide seat 700 and the valve body 100, in one embodiment, the guide seat 700 is welded to the valve body 100, or the guide seat 700 is clamped to the valve body 100. However, it is not limited thereto, and the guide seat 700 can also be threadedly connected to the valve body 100, which is not listed here one by one.

[0043] In order to ensure that the pressure oil flows smoothly from the first oil outlet channel 170 to the guide hole 710, in one embodiment, as shown in FIG. Figure 1 As shown, the valve body 100 is provided with a mounting flare 180, which is provided at one end of the first oil outlet channel 170 close to the second active plug 610, and the inner diameter of the mounting flare 180 is larger than the inner diameter of the first oil outlet channel 170, and the guide seat 700 is installed at the mounting flare 180, the inner diameter of the guide hole 710 is equal to the inner diameter of the first oil outlet channel 170, and the guide hole 710 is coaxially arranged with the first oil outlet channel 170. In this way, the flow rate of the pressure oil can be kept stable during the process of the pressure oil flowing from the first oil outlet channel 170 to the guide hole 710, because the pressure oil will not generate vortex during the flow process.

[0044] In order to improve the installation convenience of the guide seat 700, in one embodiment, as Figure 2 As shown, a stop flange 730 is provided at one end of the guide seat 700 close to the second movable plug 610, and the stop flange 730 stops at the edge of the installation expansion opening 180 close to the second movable plug 610. In this way, the guide seat 700 can be clamped at the installation expansion opening 180 by the stop flange 730 during installation, thereby achieving the installation positioning of the guide seat 700.

[0045] In order to release the pressure in the control valve in time, in one embodiment, Figure 1 As shown, the valve body 100 is also provided with a second oil outlet channel 190, and the main oil inlet channel 120 is connected to the second oil return channel 160 through the second oil outlet channel 190, and the control valve is equipped with a unloading valve 800. Normally, the unloading valve 800 closes the second oil outlet channel 190. When the pressure oil in the main oil inlet channel 120 needs to be unloaded, the unloading valve 800 opens the second oil outlet channel 190 to connect the main oil inlet channel 120 and the second oil return channel 160.

[0046] The present application also provides a rice transplanter, which includes the control valve described in any one of the above embodiments.

[0047] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0048] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of patent protection of the present application shall be subject to the attached claims.

Claims

1. A control valve, characterized in that: The invention comprises a valve body (100) and a valve stem (200); the valve body (100) is provided with a valve cavity (110), a main oil inlet passage (120), a first oil distribution passage (130), a second oil distribution passage (140), a first oil return passage (150), a second oil return passage (160) and a first oil outlet passage (170); the main oil inlet passage (120) is connected to the first oil distribution passage (130) and the second oil distribution passage (140) through the valve cavity (110); the first oil return passage (150) is connected to the first oil distribution passage (130) through the valve cavity (110); the second oil return passage (160) is connected to the second oil distribution passage (140) through the valve cavity (110); and the main oil inlet passage (120) is connected to the first oil return passage (150) through the first oil outlet passage (170); The valve stem (200) is movably disposed in the valve chamber (110); when the valve stem (200) controls the main oil inlet passage (120) to be connected to the first oil distribution passage (130), the second oil distribution passage (140) is connected to the second oil return passage (160); when the valve stem (200) controls the main oil inlet passage (120) to be connected to the second oil distribution passage (140), the first oil distribution passage (130) is connected to the first oil return passage (150); The control valve is equipped with a pressure limiting valve (600). When the hydraulic pressure value of the pressure oil in the main oil inlet channel (120) is greater than a preset pressure value, the pressure limiting valve (600) opens the first oil outlet channel (170) to connect the main oil inlet channel (120) and the first oil return channel (150).

2. The control valve according to claim 1, characterized in that: The pressure-limiting valve (600) comprises a second movable plug (610) and a second resetting elastic member (620) connected to one end of the second movable plug (610), wherein the second resetting elastic member (620) can push the second movable plug (610) to block the first oil outlet channel (170).

3. The control valve according to claim 2, characterized in that: A guide seat (700) is provided on one side of the first oil outlet passage (170) close to the second movable plug (610), and the guide seat (700) is provided with a guide hole (710) communicating with the first oil outlet passage (170). The second movable plug (610) comprises a conical head (613) and a main body (614) fixed to one end of the head (613) away from the guide seat (700), and the head (613), the main body (614) and The guide hole (710) is coaxially arranged, and when the second movable plug (610) blocks the first oil outlet channel (170), the head (613) is partially inserted into the guide hole (710); the outer diameter of the main body (614) is larger than the maximum outer diameter of the head (613), and a jet groove (615) is provided on one end surface of the main body (614) close to the head (613), and the opening of the jet groove (615) faces the head (613).

4. The control valve according to claim 3, characterized in that: The guide seat (700) is provided with a circle of annular inclined surfaces (720), and the annular inclined surfaces (720) are arranged at the opening of the guide hole (710) close to one end of the second movable plug (610).

5. The control valve according to claim 3, characterized in that: The hardness of the guide seat (700) is greater than the hardness of the valve body (100); and / or the material of the guide seat (700) is medium carbon steel.

6. The control valve according to claim 5, characterized in that The guide seat (700) is welded to the valve body (100), or the guide seat (700) is clamped to the valve body (100).

7. The control valve according to claim 3, characterized in that: The valve body (100) is provided with a mounting flare (180), and the mounting flare (180) is provided at one end of the first oil outlet channel (170) close to the second movable plug (610), and the inner diameter of the mounting flare (180) is larger than the inner diameter of the first oil outlet channel (170), and the guide seat (700) is installed at the mounting flare (180), the inner diameter of the guide hole (710) is equal to the inner diameter of the first oil outlet channel (170), and the guide hole (710) is coaxially arranged with the first oil outlet channel (170).

8. The control valve according to claim 7, characterized in that: A stop flange (730) is provided at one end of the guide seat (700) close to the second movable plug (610), and the stop flange (730) stops at an edge of the installation expansion opening (180) close to the second movable plug (610).

9. The control valve according to claim 1, characterized in that: The control valve further comprises a first resetting elastic member (400), wherein the first resetting elastic member (400) is connected to one end of the valve stem (200), and one end of the valve stem (200) connected to the first resetting elastic member (400) extends out of the valve cavity (110).

10. A rice transplanter, characterized in that: Comprising a control valve as described in any one of claims 1-9.

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