CN1540173A

CN1540173A - Quiet type throttling grooves in hydraulic component

Info

Publication number: CN1540173A
Application number: CNA2003101083817A
Authority: CN
Inventors: 新傅; 傅新; 冀宏; 杨华勇
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2003-10-30
Filing date: 2003-10-30
Publication date: 2004-10-27

Abstract

A silence-type throttle groove in hydraulic element for controlling noise is disclosed. Two throttle grooves with respective shapes and cross-sections are made on the circular shoulder of valve core and are matched with the throttle edge of the circular sealing boss on valve body to form a regulatable throttle valve mouth. Said throttle grooves has the front and back cross-sections which are different for forming a two-stage throttle channel, which can prevent the escape and growth of air bubble, so reducing noise.

Description

Calm type throttling groove in the hydraulic element

Affiliated technical field

The present invention relates to a kind of throttle valve, relate in particular to calm type throttling groove in a kind of hydraulic element.

Background technique

Throttling groove is a kind of basic hydraulic pressure valve port form, is widely used in the flow pair of hydraulic control components such as throttle valve, directional throttle valve and Hydraulic power units (comprising oil hydraulic pump, oil hydraulic motor).The setting of throttling groove depends primarily on the requirement of spool travel Flow characteristics, and fitness for purpose has the advantages that approximately linear changes.And the shape of throttling groove and size have very big influence to the noise of valve, and throttling groove is provided with improper regular meeting and whistler occurs.The throttling groove form is a difficult point problem during domestic and international research, design are produced to The noise mechanism and rule always.There are not clear and definite throttling groove noise rating criterion and the design code can reference at present.

Mobile showing as in the throttling groove, the hydrodynamic pressure of locating near the throttling limit significantly descend, pressure rising recovery gradually more thereafter.There is the pressure lowest region near rear portion, throttling limit, this district is because the pressure reduction, be prone to separating out of micro-bubble, if at this moment in the throttling groove and subsequent pressure still lower, the bubble that the upstream pressure lowest region is separated out also can be grown up, and bubble is vanished in the higher zone of downstream pressure and very big noise just occurred subsequently.

Summary of the invention

The purpose of this invention is to provide calm type throttling grooves structure in a kind of hydraulic element, offer the throttling groove of two kinds of forms on spool, a kind of rear portion of throttling groove is the uniform section section, and the leading portion of throttling groove is a gradually expanding section; Another kind of throttling groove length is shorter, and identical with the uniform section segment length of preceding a kind of throttling groove, it is shaped as front end is semicircular even depth throttling groove.The combination of such two kinds of throttling grooves can be so that its flow placement property becomes linear approximate relationship, and main is the visible noise that significantly reduces hydrovalve.

Cavitation Noise is the main cause of throttling groove noise, liquid stream at place, throttling limit owing to shrink and streamline breaks away from wall, significantly descend near place, throttling limit hydrodynamic pressure, pressure rises gradually and recovers thereafter.We have discovered that the pressure distribution of throttling groove is to the The noise rule.The present invention is based on thought that the throttling groove pressure distribution is controlled or transformed, in conjunction with the multistage throttle controlling method, employing is provided with the second level throttling runner of uniform section section as the throttling groove runner at the throttling groove rear portion, make the pressure at a fluid stream contraction place and rear portion thereof be improved, suppress the generation of air pocket and the growth of bubble, thereby suppress noise.Because the area of passage of uniform section section is constant, the flow placement property is comparatively smooth, in order to keep flow displacement approximately linear to change, arranged that on the valve body convex shoulder a kind of front end is semicircular even depth throttling groove, its length is identical with the uniform section segment length of first kind of throttling groove.

The technical solution used in the present invention is: comprise spool, valve body, first segment chute, second throttling groove; Offer first, second throttling groove on the spool convex shoulder circumference, first, second throttling groove arranges at interval evenly on the spool convex shoulder of spool that respectively the throttling limit on the ring packing boss on first, second throttling groove and the valve body constitutes adjustable throttle orifice; The front portion of first segment chute is the cross section gradually expanding section, and the rear portion is the uniform section section, and second throttling groove is that front end is a dark throttling groove such as semicircular grade.

The useful effect that the present invention has is: the throttling groove rear portion has the uniform section section, as the two-step throttle runner in the throttling groove, low pressure area to a fluid stream separation point place and rear portion thereof boosts, and so both can improve the pressure of point of flow separation, can accelerate pressure recovery again.Can reduce separating out of bubble thus, can stop the growth of bubble to become big again.Therefore can reduce noise effectively.The present invention is applicable to the noise control of the hydraulic control component of various throttling grooves structure forms, the principle novelty, simple in structure, noise reduction is remarkable.

Description of drawings

Fig. 1 is a structural principle schematic representation of the present invention;

Fig. 2 is the B-B sectional view of Fig. 1;

Fig. 3 is the local enlarged diagram of the A of Fig. 1;

Fig. 4 is that the D of Fig. 3 is to partial schematic diagram;

Fig. 5 is that the E of Fig. 3 is to partial schematic diagram;

Fig. 6 is that the D of Fig. 3 is to partial schematic diagram;

Fig. 7 is that the E of Fig. 3 is to partial schematic diagram;

Fig. 8 is the local enlarged diagram of the C of Fig. 2;

Fig. 9 is that the F of Fig. 8 is to partial schematic diagram;

Figure 10 is that the G of Fig. 8 is to partial schematic diagram.

Among the figure: 1. spool, 2. valve body, 3. first segment chute, 4. spool convex shoulder, the 5. seal boss in the valve body, 6. throttling limit, 7. second throttling groove, 8. first throttle slot cross-section gradually expanding section, 9. first segment chute uniform section section.

Embodiment

As Fig. 1～shown in Figure 10, the present invention includes: comprise spool 1, valve body 2, first segment chute, second throttling groove 7; Offer first segment chute, second throttling groove 7 on the spool 1 convex shoulder circumference, first segment chute, second throttling groove 7 arrange at interval evenly on the spool convex shoulder 4 of spool 1 that respectively the throttling limit 6 on the ring packing boss 5 on first segment chute, second throttling groove 7 and the valve body 2 constitutes adjustable throttle orifice; The front portion of first segment chute is a cross section gradually expanding section 8 or 8 ', and the rear portion is that uniform section section 9 or 9 ', the second throttling groove 7 is that front end is a dark throttling groove such as semicircular grade.

The shape of first segment chute has two kinds, and promptly the cross section is that triangle 3 or cross section are rectangle 3 ' (as Fig. 5 or shown in Figure 7).

The uniform section section 9 of first segment chute or 9 ' length are 0.2～0.5 times (as Fig. 4 or shown in Figure 6) of first segment chute total length.

The cross section gradually expanding section 8 or 8 ' of first segment chute is triangle or rectangle (as Fig. 4 or shown in Figure 6).

The length of second throttling groove 7 and the uniform section section 9 of first segment chute or 9 ' length identical (as Fig. 4 or Fig. 6 and shown in Figure 9).

Working procedure of the present invention is as follows:

High pressure oil through throttling groove 3 or 3 ' and the valve port that constitutes of throttling limit 6, enters the oil return undercut groove by the oil-feed undercut groove.Because the valve port throttling action makes a fluid stream the minimum pressure district occur near 6 places, throttling limit, when a fluid stream flow further downstream is passed through uniform section section 9 or 9 ', can be subjected to the flow resistance effect, valve port opening is more little, and resistance length is long more, and its resistance will make the minimal pressure force raise; When valve port opening was big, under the same pressure differential situation, flow can increase, and also can make flow resistance increase, and made a fluid stream contraction place pressure raise equally.Therefore, great changes have taken place in the pressure distribution in the throttling groove, and a fluid stream separation point pressure and pressure recovery region pressure are all raise, and bubble is separated out and the process of growing up is effectively suppressed, and the valve noise significantly reduces.

Claims

1. calm type throttling groove in the hydraulic element is characterized in that: comprise spool (1), valve body (2), first segment chute, second throttling groove (7); Offer first segment chute, second throttling groove (7) on spool (1) the convex shoulder circumference, first segment chute, second throttling groove (7) are gone up evenly at the spool convex shoulder (4) of spool (1) respectively and are arranged that at interval the throttling limit (6) on the ring packing boss (5) on first segment chute, second throttling groove (7) and the valve body (2) constitutes adjustable throttle orifice; The front portion of first segment chute is cross section gradually expanding section (8), and the rear portion is uniform section section (9), and second throttling groove (7) is that front end is a dark throttling groove such as semicircular grade.

2. calm type throttling groove in the hydraulic element according to claim 1 is characterized in that: the shape of first segment chute has two kinds, and promptly the cross section is that triangle (3) or cross section are rectangle (3 ').

3. calm type throttling groove in the hydraulic element according to claim 1 is characterized in that: the length of the uniform section section (9 or 9 ') of first segment chute is 0.2～0.5 times of first segment chute total length.

4. calm type throttling groove in the hydraulic element according to claim 1 is characterized in that: the cross section gradually expanding section (8 or 8 ') of first segment chute is triangle or rectangle.

5. calm type throttling groove in the hydraulic element according to claim 1 is characterized in that: second throttling groove (7) length is identical with the length of the uniform section section (9 or 9 ') of first segment chute.