Built-in speed limiting valve

Abstract

The built-in speed limiting valve comprises a valve body and a valve element, a baffle is installed at the open end of the valve body, an elastic blocking assembly is arranged between the baffle and the valve element, and an elastic supporting assembly is arranged between the valve element and a base of the valve body; a plurality of inner liquid passing holes are evenly distributed in the side wall of a main body part of the valve body in the circumferential direction, a plurality of outer liquid passing holes are evenly distributed in the side wall of the valve body in the circumferential direction, annular liquid control grooves corresponding to the inner liquid passing holes are formed in the valve element, the liquid control grooves are communicated with an inner cavity of the valve element through a plurality of control holes, and the width value of the liquid control grooves is larger than the diameter of the inner liquid passing holes. The diameter of the control hole is smaller than that of the inner liquid passing hole. The structure is simple, when the oil pressure difference changes greatly, the instantaneous change of the oil pressure can be effectively compensated, the fluctuation of the valve element is reduced to the maximum extent, then the stability of the flow is kept, and the effect of controlling the moving speed of the oil cylinder to be stable is achieved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of hydraulic technology, and particularly relates to an internal speed limiting valve. BACKGROUND

[0002] The speed limiting valve is a commonly used valve in a hydraulic control system, and is widely applied in lifting and lowering of a fork of a forklift. The speed limiting valve mainly comprises a cylindrical valve body with a control valve core, a valve core spring, a valve sleeve, and a movable valve core in the valve sleeve. The valve core is brought to its working position by fluid flowing therethrough, and the throttling resistance related to the pre-pressure of the valve core spring determines the regulated flow value. When flowing in the opposite direction, the valve core completely returns from its regulating position, the flow through the speed limiting valve is irrelevant to the regulating range of the valve core, and only the medium is discharged from the flow limiting hole, thereby playing a function similar to that of a one-way valve. Most of the existing speed limiting valves are of an external structure, and have a relatively complex structure, high processing and use costs, and great impact of oil pressure on the valve core in an instant, so that the oil pressure is instantaneously fluctuated, and the flow stability is affected. Therefore, it is necessary to improve the existing speed limiting valve. SUMMARY

[0003] In view of this, the present application aims to overcome the defects in the prior art, and provides an internal speed limiting valve.

[0004] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0005] An internal speed limiting valve comprises a valve body with one end being open, a valve core is installed in the valve body, the valve core is in sliding fit with the inner wall of the valve body, an expanding section is arranged on one side of the inner cavity of the valve body close to the base, and the diameter of the expanding section is greater than that of the inner cavity of the main body part of the valve body; a baffle is installed on the open end of the valve body, an elastic separation and blocking assembly is arranged between the baffle and the valve core, and an elastic supporting assembly is arranged between the valve core and the base of the valve body; the elastic supporting assembly comprises an outer spring, an annular supporting table for supporting the outer spring is arranged on the base, a buffer inner groove is formed on the inner side of the annular supporting table, a buffer outer ring groove is formed between the outer side of the annular supporting table and the inner wall of the valve body, and an inclined side wall is arranged on the outer side of the annular supporting table.

[0006] The elastic separation and blocking assembly comprises a steel ball arranged between the valve core and the baffle, a buffer liquid passing hole corresponding to the steel ball is arranged on the baffle, an inner spring for abutting against the steel ball is arranged in the groove at the bottom of the valve core; a plurality of inner liquid passing holes are uniformly arranged on the side wall of the main body part of the valve body in the circumferential direction, a plurality of outer liquid passing holes are uniformly arranged on the side wall of the valve body in the circumferential direction, an annular liquid control groove is arranged on the valve core corresponding to the inner liquid passing holes, the liquid control groove and the inner cavity of the valve core are communicated through a plurality of control holes, the width value of the liquid control groove is greater than the diameter of the inner liquid passing hole, and the diameter of the control hole is smaller than that of the inner liquid passing hole.

[0007] Further, the buffer inner groove is an arc-shaped groove.

[0008] Further, each control hole is arranged symmetrically with the valve core axis.

[0009] Further, the control liquid groove width value is 2-3 times of the inner liquid passage hole diameter value.

[0010] Further, the valve body outer wall is provided with an outer connecting section and an inner connecting section, the outer connecting section is located on the upper side of the outer liquid passage hole, and the inner connecting section is located on the lower side of the outer liquid passage hole.

[0011] Further, the outer connecting section and the inner connecting section adopt the same specification of external thread structure.

[0012] Further, the number of the inner liquid passage hole and the outer liquid passage hole is the same, and the diameter of the inner liquid passage hole and the outer liquid passage hole is the same.

[0013] Further, the valve body outer wall is provided with an end cap on the side of the base, and a sealing ring is arranged on the lower side of the end cap.

[0014] Compared with the prior art, the present application has the following advantages:

[0015] The present application has the advantages of simple structure, by arranging the inner liquid passage hole and the outer liquid passage hole on the valve body side wall, and arranging the control liquid groove matched with the inner liquid passage hole on the valve core, the control liquid groove is communicated with the valve core inner cavity through the control liquid hole, the elastic support assembly is arranged above the valve core, and the elastic barrier assembly is arranged below the valve core, if the oil pressure difference changes greatly, not only the outer spring can buffer the impact of the valve core, but also the oil can open the steel ball, after the steel ball of the elastic barrier assembly is opened instantaneously, the buffer liquid passage on the baffle is conducted to compensate the instantaneous change of the pressure, the valve core fluctuation is minimized, and the flow stability is maintained, thereby playing a role in controlling the smooth movement of the oil cylinder. BRIEF DESCRIPTION OF DRAWINGS

[0016] The drawings constituting a part of the present application are used to provide a further understanding of the present application, the schematic embodiment of the present application and its description are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 It is a structural schematic diagram of the present application;

[0018] Figure 2 It is Figure 1 It is a schematic diagram of the valve body part in the present application;

[0019] Figure 3 It is a schematic diagram of the valve body part in the present application;

[0020] Figure 4 It is Figure 3 It is a schematic diagram of the base part of the valve body in the present application;

[0021] Figure 5 This is a schematic diagram of the valve core portion in this invention. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] A built-in speed limiter valve, such as Figures 1 to 5 As shown, the valve body 1 is open at one end, and a valve core 2 is installed inside the valve body. The valve core slides against the inner wall of the valve body. An expansion section 3 is provided on the side of the valve body cavity near the base. The diameter of the expansion section is larger than the inner diameter of the valve body body. A baffle 4 is installed at the open end of the valve body. An elastic partition assembly 5 is provided between the baffle and the valve core, and an elastic support assembly 6 is provided between the valve core and the base of the valve body.

[0027] The specific structure of the valve body is as follows: the outer wall of the valve body is provided with an end cap on the side of the base, and a sealing ring is provided on the lower side of the end cap. When the built-in speed limit valve is installed in place, the end cap abuts against the installation step, and the sealing ring plays a good sealing role.

[0028] The elastic support assembly can form elastic support for the lower part of the valve core, and the elastic support assembly can form elastic support for the upper part of the valve core, so that the valve core can be buffered when the oil pressure changes. Generally, the elastic support assembly includes an outer spring 7, the elastic support assembly includes a steel ball 12 arranged between the valve core and the baffle, a buffer liquid passage 13 corresponding to the steel ball is arranged on the baffle, and an inner spring 14 for abutting against the steel ball is arranged in the groove at the bottom of the valve core. The open end of the valve body is provided with a limiting piece 15 for limiting the baffle, and the limiting piece is an elastic baffle ring arranged in the hole of the inner wall of the valve body.

[0029] An annular support table 8 for supporting the outer spring is arranged on the base, and a buffer inner groove 9 is formed on the inner side of the annular support table. The buffer inner groove is an arc-shaped groove. A buffer outer ring groove 10 is formed between the outer side of the annular support table and the inner wall of the valve body, and the side wall of the outer side of the annular support table is a slope 11. By designing the buffer inner groove and the buffer outer ring groove on the base of the valve body and designing the side wall of the annular support table as a slope, the buffer effect can be effectively achieved, the oil impact can be reduced, the vibration and noise can be reduced, and the stability of the built-in speed limiting valve during use can be improved.

[0030] A plurality of inner liquid passages 16 are arranged on the side wall of the main body portion of the valve body in the circumferential direction, and a plurality of outer liquid passages 17 are arranged on the side wall of the valve body in the circumferential direction. A ring-shaped liquid control groove 18 is arranged on the valve core corresponding to the inner liquid passages, the liquid control groove is communicated with the inner cavity of the valve core through a plurality of control holes 19, and the control holes are arranged in the circumferential direction and are equidistantly arranged with the valve core axis as the center. The width of the liquid control groove is greater than the diameter of the inner liquid passage, and the diameter of the control hole is smaller than the diameter of the inner liquid passage.

[0031] For example, the width of the liquid control groove is 2-3 times the diameter of the inner liquid passage. During use, the oil entering the inside of the valve body through the inner liquid passage will gather at the liquid control groove, and part of the oil will enter the valve core through the control hole and then be discharged from the outer liquid passage. If the oil enters from the outer liquid passage and is discharged from the inner liquid passage, the valve core does not participate in the process.

[0032] The outer wall of the valve body is provided with an outer connecting section 20 and an inner connecting section 21. The outer connecting section is located above the outer liquid passage, and the inner connecting section is located below the outer liquid passage. For example, the outer connecting section and the inner connecting section adopt the same specification of external thread structure. The connecting sections of the outer wall of the valve body can be used to conveniently install the speed limiting valve in the valve hole. Generally, the number of inner liquid passages and outer liquid passages is the same, and the diameters of the inner liquid passages and the outer liquid passages are the same.

[0033] Working principle:

[0034] (1) Oil flows in the positive direction: when the oil enters from the outer liquid passage and is discharged from the inner liquid passage, the outer liquid passage and the inner liquid passage are equivalent to direct conduction, and the valve core does not work.

[0035] (2) Oil liquid reverse flow: when the oil liquid enters from the inner liquid hole and discharges from the outer liquid hole, when the external load changes, the oil liquid pressure at the inner liquid hole position changes, the oil liquid enters the inner part of the valve core from the inner liquid hole, the pressure difference between the inner and outer changes, under the joint action of the inner and outer springs, the valve core moves to the outer liquid hole (when the pressure difference increases) or the inner liquid hole (when the pressure difference decreases) to change the size of the valve core blocking the valve body through hole section, and then keep the flow per unit time stable, realize the constant moving speed of the oil cylinder, and play the role of speed limiting.

[0036] The application has simple structure, the inner liquid hole and the outer liquid hole are arranged on the side wall of the valve body, the liquid control groove matched with the inner liquid hole is arranged on the valve core, the liquid control groove is communicated with the inner cavity of the valve core through the liquid control hole, the elastic support assembly is arranged above the valve core, and the elastic barrier assembly is arranged below the valve core, if the oil liquid pressure difference changes greatly, the outer spring can buffer the impact of the valve core, and the steel ball is allowed to be opened by the oil liquid, after the steel ball of the elastic barrier assembly is opened instantaneously, the buffer liquid hole on the baffle is conducted to compensate the change of pressure, the fluctuation of the valve core is minimized, and then the stability of the flow is kept, and the moving speed of the oil cylinder is kept stable.

[0037] The above only describes the preferred embodiment of the application, and does not limit the application, any modification, equivalent replacement, improvement, etc. within the spirit and principle of the application should be included in the protection scope of the application.

Claims

1. A built-in speed limiting valve, characterized in that: The valve includes an open-end valve body with a valve core installed inside. The valve core slides against the inner wall of the valve body. An expansion section, larger in diameter than the main body's inner cavity, is located near the base of the valve body. A baffle is installed at the open end of the valve body, with an elastic partition assembly between the baffle and the valve core. An elastic support assembly is located between the valve core and the base of the valve body. The elastic support assembly includes an outer spring. An annular support platform for supporting the outer spring is located on the base. An inner buffer groove is formed on the inner side of the annular support platform, and an outer buffer groove is formed between the outer side of the annular support platform and the inner wall of the valve body. The outer side of the valve core has an inclined sidewall; the elastic baffle assembly includes a steel ball disposed between the valve core and the baffle, and a buffer liquid passage hole is provided on the baffle corresponding to the steel ball. An inner spring is provided in the groove at the bottom of the valve core to hold the steel ball in place; several inner liquid passage holes are evenly distributed along the circumference on the sidewall of the valve body, and several outer liquid passage holes are evenly distributed along the circumference on the sidewall of the valve body. An annular liquid control groove is provided on the valve core corresponding to the inner liquid passage hole. The liquid control groove is connected to the inner cavity of the valve core through several control holes. The width of the liquid control groove is greater than the diameter of the inner liquid passage hole, and the diameter of the control hole is smaller than the diameter of the inner liquid passage hole.

2. The built-in speed limiting valve according to claim 1, characterized in that: The inner groove of the buffer is an arc-shaped groove.

3. The built-in speed limiting valve according to claim 1, characterized in that: The control holes are evenly distributed with the valve core axis as the center.

4. The built-in speed limiting valve according to claim 1, characterized in that: The width of the liquid control tank is 2-3 times the diameter of the inner liquid passage hole.

5. A built-in speed limiting valve according to claim 1, characterized in that: The valve body has an outer connecting section and an inner connecting section on its outer outer liquid passage. The outer connecting section is located above the outer liquid passage, and the inner connecting section is located below the outer liquid passage.

6. A built-in speed limiting valve according to claim 5, characterized in that: Both the outer and inner connecting sections adopt the same external thread structure.

7. A built-in speed limiting valve according to claim 1, characterized in that: The number of internal and external liquid passages is the same, and the diameter of the internal and external liquid passages is the same.

8. A built-in speed limiting valve according to claim 1, characterized in that: The valve body has an end cap on the base side of its outer wall, and a sealing ring is provided on the underside of the end cap.

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