CN204323470U - A kind of low noise hydraulic steering gear - Google Patents

Abstract

The utility model relates to a low-noise hydraulic steering gear, which belongs to the technical field of hydraulic pressure. The steering gear has an oil inlet ring groove of the valve body and is equipped with a valve sleeve and a valve core. One end of the valve sleeve has an oil return hole for the valve sleeve, and the middle section of the valve sleeve has an oil distribution hole for the valve sleeve. There is a valve sleeve oil inlet hole between the oil holes; one end of the valve core has a group of oil return holes of the valve core corresponding to the position of the oil return hole of the valve sleeve at circumferential intervals, and the valve core has an oil distribution ring groove corresponding to the position of the oil inlet hole of the valve sleeve , the oil distribution ring groove circumferentially extends a group of communication grooves corresponding to the position of the oil distribution hole of the valve sleeve; There is a buffer groove with an axial extension longer than the flow length of the oil return hole. Because the closure or connection of the oil return hole in the utility model will become gentle due to the gradual transition of the intermediate state, the flow rate and pressure of the hydraulic oil are relatively soft, and the noise is effectively reduced as a result.

Description

A low-noise hydraulic steering gear

technical field

The utility model relates to a steering gear, in particular to a low-noise hydraulic steering gear, which belongs to the technical field of hydraulic pressure.

Background technique

The hydraulic steering gear is a steering control device commonly used in construction machinery, agricultural machinery and other engineering vehicles. It is mainly composed of rotor stator meshing pair, valve body, valve core sleeve assembly and other components. Wherein, the valve core sleeve assembly is composed of a valve core and a valve sleeve, and the valve core is installed inside the valve sleeve. For further understanding of the specific structure and working principle of the steering gear, please refer to the Chinese patent document with application number 200810020802.3, which discloses that one end of the valve body of the steering gear supports an indexable valve core, and there is a valve sleeve between the valve core and the valve body , the valve body, valve sleeve and valve core constitute a rotary valve; the other end is equipped with a cycloidal pinwheel meshing pair between the partition plate and the back cover; the inner cavity of the valve body is equipped with an indexable flow channel through the valve sleeve. Spool; the spool is equipped with a linkage shaft; one end of the linkage shaft forms a rotary valve flow distribution structure matched with the flow channel of the valve body; the other end of the linkage shaft forms a cycloid metering motor through a spline gear pair and a cycloid pin wheel meshing pair ; The flow channel on the valve body communicates with the inlet and outlet ports of the flow channel of the transfer valve distribution mechanism in the inner cavity.

As far as the applicant knows, the steering switching control of the steering gear in the prior art is very noisy. Since the interior of the steering gear involves complex mechanisms such as cycloidal pin-wheel pair and linkage transmission, the flow path is also very complicated, and there are many possible reasons for the noise. Therefore, for a long time, the above-mentioned problems have not been effectively solved, and become a technical problem, which affects the quality of the steering gear.

Utility model content

The purpose of the utility model is to propose a low-noise hydraulic steering gear by improving the structure in view of the problems in the prior art.

In order to achieve the above object, the applicant finally found out that the main noise source when the steering gear is operated comes from the oil return hole on the valve core and the valve sleeve through in-depth research and analysis and repeated test verification. In the existing steering gear, one end of the valve core is provided with a valve core oil return hole, and one end of the valve sleeve is provided with a corresponding valve sleeve oil return hole. When the steering gear is working, through the relative rotation of the valve core and the valve sleeve, the oil return holes of the valve core and the valve sleeve are connected or closed as required to realize the required flow path switching control. In this process, the connection or closure of the oil return hole is basically completed instantly, and the oil return hole is small, so it becomes the most important cause of the rapid change of the flow rate and pressure of the hydraulic oil when switching, and the result inevitably causes noise.

On the basis of this understanding, the technical scheme of the low-noise hydraulic steering gear of the present invention is proposed as follows: it includes a valve body, and the valve hole of the valve body has a valve body oil inlet ring groove and is equipped with a valve sleeve and inserted in the The indexable valve core in the valve sleeve, one end of the valve sleeve has a group of radial valve sleeve oil return holes distributed in the circumferential direction corresponding to the position of the oil inlet ring groove of the valve body, the valve sleeve The middle section of the valve body has a group of circumferentially spaced radial valve sleeve oil distribution holes communicating with the oil supply passage of the valve body. The radial valve sleeve oil inlet holes distributed in the circumferential direction corresponding to the position on the other side of the body oil inlet ring groove; one end of the valve core has a group of circumferentially spaced distribution of the valve core return hole corresponding to the position of the valve sleeve oil return hole. The oil hole, the valve core has an oil distribution ring groove corresponding to the position of the oil inlet hole of the valve sleeve, and a group of communication grooves corresponding to the position of the oil distribution hole of the valve sleeve extend from the oil distribution ring groove at circumferential intervals; it is characterized in that : At least one group of the oil return hole of the valve sleeve and the oil return hole of the valve core is formed with a buffer groove whose axial extension length is greater than the flow length of the oil return hole at each oil return hole of the corresponding group.

A further improvement of the utility model is that at least one of the two sides of the buffer tank extends to form a buffer pool whose width is greater than the flow width of the oil return hole.

It should be noted that the "hole" in the oil return hole in this application means a communication structure through which oil can flow, and the cross-sectional shape is not limited to a circle.

When working, the first position: when the spool is rotated so that the angular position of the oil return hole of the spool and the oil return hole of the valve sleeve are staggered, and it is in the off position, the communication groove on the spool will be connected with the oil inlet hole of the valve sleeve on the valve sleeve. At this time, the oil entering the oil inlet groove of the valve body flows to the oil distribution groove of the valve core through the oil inlet holes on the valve sleeve, and then passes through each communication groove and then is output to the steering oil cylinder by the corresponding oil distribution holes of the valve sleeve. , to achieve the required steering control; the second position: when the spool is rotated to align the oil return hole of the spool with the angular position of the oil return hole of the valve sleeve, it is in the communication position, and the communication groove on the spool will align with the valve sleeve on the valve sleeve. The sleeve is equipped with oil hole separation. At this time, the oil entering the oil inlet groove of the valve body flows into the valve core through the oil return holes on the valve sleeve and the corresponding oil return holes of the valve core, and flows back to the oil tank through the oil return groove.

Different from the prior art, in the process of switching between the first and second positions, the oil return holes are no longer directly and instantly aligned and communicated, and before the alignment and communication, they first pass through the buffer pool and/or buffer tank Communication, so the closure or communication of the oil return hole will become gentle due to the gradual transition of the intermediate state, so that the flow rate and pressure of the hydraulic oil will change softer, and the noise will be effectively reduced.

It can be seen that the utility model has found the crux of the noise, so it adopts a simple structure that is easy to realize in the process, and effectively achieves the purpose.

Description of drawings

Fig. 1 is the structural representation of the utility model embodiment one.

Fig. 2 is a schematic diagram of the structure of the valve core in Embodiment 1 of the present utility model.

Figure 3 is a schematic diagram of the C-C cross-sectional structure of Figure 2.

Fig. 4 is a schematic structural diagram of the valve sleeve of the second embodiment of the utility model.

FIG. 5 is a schematic diagram of the B-B cross-sectional structure of FIG. 4 .

Fig. 6 is a schematic diagram of the structure of the valve sleeve in Embodiment 1 of the present utility model.

Fig. 6' is a partially expanded schematic view of the valve sleeve corresponding to Fig. 6 .

Fig. 7 is a schematic diagram of the structure of the valve core in Embodiment 1 of the present utility model.

Fig. 7' is a partially developed schematic view of the valve core corresponding to Fig. 7 .

Fig. 8 is a schematic diagram showing the relative closed positions of the valve sleeve and the valve core in Embodiment 1 of the present invention.

Fig. 8' is a schematic diagram showing the relative communication positions of the valve sleeve and the valve core in Embodiment 1 of the present invention.

Fig. 9 is a schematic diagram of the structure of the valve sleeve of the second embodiment of the utility model.

Fig. 9' is a partially developed schematic view of the valve sleeve corresponding to Fig. 9 .

Fig. 10 is a schematic diagram of the structure of the valve core in the second embodiment of the present invention.

Fig. 10' is a partially developed schematic view of the valve core corresponding to Fig. 10 .

Fig. 11 is a schematic diagram showing the relative closed positions of the valve sleeve and the valve core in the second embodiment of the present invention.

Fig. 11' is a schematic diagram showing the relative communication positions of the valve sleeve and the valve core in the second embodiment of the present invention.

Detailed ways

Embodiment one

The low-noise hydraulic steering gear of this embodiment is shown in Figure 1. Its basic structure is the same as that of the prior art. The right end of the valve body is equipped with a cycloid pinwheel engagement pair 6 between the partition plate 4 and the rear cover 5. The inner hole of the valve body 1 has a valve body oil inlet ring groove 9 and is installed with an indexable valve core 3 with a flow channel through the valve sleeve 2, or in other words, the valve hole of the valve body 1 is equipped with a valve sleeve 2 and a cartridge Indexable spool 3 in the valve sleeve. The valve core 3 is equipped with a linkage shaft 7, and one end of the linkage shaft 7 is respectively connected with the valve sleeve 2 and the valve core 3 through the dial pin 8 and the elastic member to form a rotary valve flow distribution mechanism matched with the flow channel of the valve body 1. The other end of the linkage shaft 7 is connected to the cycloidal pinwheel meshing pair 6 through a spline gear pair to form a cycloid metering motor. The valve body 1 has an oil inlet and an outlet which can be communicated with the flow path of the internal cavity relay valve flow distribution mechanism.

Referring to Figure 6 and Figure 6', the valve sleeve 2 of this embodiment is basically the same as the prior art, and one end has a set of circumferential intervals corresponding to the position on the right side of the valve body oil inlet ring groove 9 of the valve body 1 in Figure 1 There are two rows of twelve radial valve sleeve small-diameter oil return holes 2-1, and the middle section of the valve sleeve 2 has a set of twelve radial valve sleeves distributed in circumferential intervals that communicate with the oil supply channel of the valve body 1. Oil hole 2-2. Between the small-diameter oil return hole 2-1 of the valve sleeve 2 and the oil distribution hole 2-2 of the valve sleeve, there is a group of twelve radial valves distributed at circumferential intervals corresponding to the position on the left side of the oil inlet ring groove 9 of the valve body. Set into the oil hole 2-3.

As shown in Fig. 2 and Fig. 3 and referring to Fig. 7 and Fig. 7', the spool 3 has a set of twelve spool oil return slots distributed circumferentially at intervals corresponding to the position of the oil return round hole 2-1 of the valve sleeve 2 3-1, and each valve core oil return groove hole 3-1 is formed with a buffer groove 3-A whose axial extension length L is greater than the flow length l of the valve core oil return groove hole 3-1. These buffer grooves 3-A extend angularly to four sides separated by 90°, resulting in a buffer pool 3-A' whose width W is greater than the flow width w of the oil return groove hole of the spool. The position of the valve core 3 corresponding to the oil inlet hole 2-3 of the valve sleeve 2 has an oil distribution ring groove 3-3, and the oil distribution ring groove 3-3 extends in a circumferential interval to a group corresponding to the position of the valve sleeve oil distribution hole 2-2. Connecting groove 3-2.

During the working process, when the rotary valve flow distribution mechanism is in the first position through motion transmission, as shown in Figure 8, the valve core 3 makes the oil return groove hole 3-1 of the valve core and the oil return hole 2-1 of the valve sleeve 2 angularly staggered , in the off position, the communication groove 3-2 on the valve core 3 will communicate with the valve sleeve oil distribution hole 2-2 on the valve sleeve 2, at this time, the oil entering the oil inlet groove 9 of the valve body 1 passes through Each oil inlet hole 2-3 flows to the valve core oil distribution groove 3-3, and then through each communication groove 3-2, the output is supplied to the steering oil cylinder by the corresponding valve sleeve oil distribution hole 2-2 to realize the required steering control. When it is in the second position, as shown in Figure 9, the spool 3 aligns the angular position of the oil return groove 3-1 of the spool with the oil return hole 2-1 of the valve sleeve, and is in the communication position. The communication groove on the spool 3 3-2 will be separated from the valve sleeve oil distribution hole 2-2 on the valve sleeve 2. At this time, the oil entering the oil inlet groove 9 of the valve body 1 will pass through each oil return hole 2-1 on the valve sleeve 2 and each corresponding oil return hole 2-1. The spool oil return groove hole 3-1 flows into the spool 2, and flows back to the oil tank through the oil return groove 3-4.

During the switching process of the first and second positions, the oil return hole 2-1 of the valve sleeve first communicates with the buffer pool 3-A' on the valve core 3, and then communicates with the oil return groove hole 3-1 of the valve core through the transition of the buffer tank. Therefore, the communication becomes gentle due to the gradual transition of the intermediate communication state, and the flow rate and pressure of the hydraulic oil are significantly slowed down, thus effectively reducing the noise.

Embodiment two

The basic structure of the low-noise hydraulic steering gear of this embodiment is the same as that of Embodiment 1. The difference is the specific structure of the valve sleeve 2 and the valve core 3 .

The valve sleeve 2 of this embodiment is shown in Fig. 4 and Fig. 5, referring to Fig. 9 and Fig. 9', one end has a set of circumferential direction corresponding to the position on the right side of the valve body oil inlet ring groove 9 of the valve body 1 in Fig. 1 Two rows of twelve pairs of radial valve sleeve oil return groove holes 2-1 distributed at intervals. Each valve sleeve oil return groove hole 2-1 is made of round counterbore 2-1-1 and the slot 2-1-2 at the bottom of round counterbore. The outer mouth of each pair of round counterbore 2-1-1 is shaped on the accumulator 2-1-3 of circular arc bottom. The slot 2-1-2 of the oil return groove hole 2-1 of the valve sleeve is formed with an arc bottom buffer groove 2-A whose axial extension length L is greater than the sum of the flow length l of the oil return groove holes 2-1 of the two valve sleeves.

The middle section of the valve sleeve 2 has a group of twelve radial valve sleeve oil distribution holes 2-2 communicated with the oil supply passage of the valve body 1 at intervals in the circumferential direction. Between the oil return groove hole 2-1 of the valve sleeve 2 and the oil distribution hole 2-2 of the valve sleeve, there is a group of twelve radial valve sleeve inlets distributed at circumferential intervals corresponding to the position on the left side of the oil inlet ring groove 9 of the valve body. Oil holes 2-3.

The structure of the spool 3 is shown in Fig. 10 and Fig. 10', and one end has a set of twelve spool oil return slots 3-1 corresponding to the position of the oil return circular slot 2-1 of the valve sleeve 2 at intervals in the circumferential direction. And each valve core oil return groove hole 3-1 is shaped with an arc bottom buffer groove 3-A whose axial extension length L is greater than the flow length l of the valve core oil return groove hole 3-1. These buffer grooves 3-A extend towards both sides, and as a result form a buffer pool 3-A' whose width W is greater than the flow width w of the spool oil return groove hole 3-1. The position of the valve core 3 corresponding to the oil inlet hole 2-3 of the valve sleeve 2 has an oil distribution ring groove 3-3, and the oil distribution ring groove 3-3 extends in a circumferential interval to a group corresponding to the position of the valve sleeve oil distribution hole 2-2. Connecting groove 3-2.

During the working process, when the rotary valve flow distribution mechanism is in the first position through motion transmission, as shown in Figure 11, the valve core 3 makes the oil return groove hole 3-1 of the valve core and the oil return groove hole 2-1 of the valve sleeve 2 angularly staggered , in the off position, the communication groove 3-2 on the valve core 3 will communicate with the valve sleeve oil distribution hole 2-2 on the valve sleeve 2, at this time, the oil entering the oil inlet groove 9 of the valve body 1 passes through Each oil inlet hole 2-3 flows to the valve core oil distribution groove 3-3, and then through each communication groove 3-2, the output is supplied to the steering oil cylinder by the corresponding valve sleeve oil distribution hole 2-2 to realize the required steering control. When it is in the second position, as shown in Figure 11', the spool 3 aligns the oil return groove hole 3-1 of the spool with the oil return groove hole 2-1 of the valve sleeve, and is in the communication position. The communication on the spool 3 The groove 3-2 will be separated from the valve sleeve oil distribution hole 2-2 on the valve sleeve 2. At this time, the oil entering the oil inlet groove 9 of the valve body 1 will pass through the oil return holes 2-1 on the valve sleeve 2 and the corresponding oil return holes 2-1. Each spool oil return groove hole 3-1 flows into the spool 2, and flows back to the oil tank through the oil return groove 3-4.

During the switching process of the first and second positions, the oil return groove hole 2-1 of the valve sleeve first communicates with the buffer pool 3-A' on the valve core 3, and then communicates with the oil return groove hole 3-1 of the valve core through the transition of the buffer tank. Therefore, the communication becomes smoother due to the gradual transition of the intermediate communication state, and the flow velocity and pressure of the hydraulic oil are significantly slowed down. Tests have proved that this "slot-to-slot" communication switching structure is the same as that of the first embodiment "circle". The noise reduction effect of the connected switching structure of "hole to slot hole" is better.

In addition to the above embodiments, the utility model can also have other implementations. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the utility model.

Claims (10)

1. A low-noise hydraulic steering gear, comprising a valve body, the valve hole of the valve body has a valve body oil inlet ring groove and is equipped with a valve sleeve and an indexable valve core inserted in the valve sleeve, One end of the valve sleeve has a set of circumferentially spaced radial valve sleeve oil return holes corresponding to one side of the oil inlet ring groove of the valve body, and the middle section of the valve sleeve has a set of The oil supply channel communicates with radial valve sleeve oil distribution holes distributed at intervals in the circumferential direction. There is a group between the valve sleeve oil return hole and the valve sleeve oil distribution hole corresponding to the position on the other side of the oil inlet ring groove of the valve body. The radial valve sleeve oil inlet holes distributed at circumferential intervals; one end of the valve core has a set of valve core oil return holes distributed at circumferential intervals corresponding to the positions of the valve sleeve oil return holes, and the valve core corresponds to the position of the valve sleeve The position of the oil inlet hole has an oil distribution ring groove, and the oil distribution ring groove extends circumferentially at intervals to a group of communication grooves corresponding to the position of the oil distribution hole of the valve sleeve; it is characterized in that: at least the oil return hole of the valve sleeve and the One group of the oil return holes of the valve core is formed with buffer grooves whose axial extension length is greater than the flow length of the oil return holes corresponding to each oil return hole of the group. 2. The low-noise hydraulic steering gear according to claim 1, characterized in that: at least one of the two sides of the buffer groove extends to form a buffer pool with a width greater than the flow width of the oil return hole. 3. The low-noise hydraulic steering gear according to claim 1, characterized in that: one end of the valve sleeve has a group of two rows of radial valve sleeves distributed in circumferential intervals corresponding to the position on the right side of the oil inlet ring groove of the valve body Oil return round hole; one end of the spool has a group of oil return grooves distributed at circumferential intervals corresponding to the position of the oil return round hole of the valve sleeve, and the oil return groove of the spool is made with a Buffer tank for return tank bore flow length. 4. The low-noise hydraulic steering gear according to claim 3, characterized in that: the buffer tank extends on four sides angularly separated by 90° to form a buffer with a width greater than the flow width of the oil return groove hole of the valve core pool. 5. The low-noise hydraulic steering gear according to claim 1, characterized in that: one end of the valve sleeve has a set of two row diameters corresponding to the position on the right side of the oil inlet ring groove of the valve body in the circumferential direction. To the oil return groove hole of the valve sleeve, the oil return groove hole of the valve sleeve is composed of a round counterbore and a slot at the bottom of the round counterbore. 6. The low-noise hydraulic steering gear according to claim 5, characterized in that: each pair of round counterbore holes in the two rows of round counterbore holes has an arc-bottomed accumulator at its outer opening. 7. The low-noise hydraulic steering gear according to claim 6, characterized in that: the slot of the oil return slot of the valve sleeve is made with an axial extension length greater than the sum of the two flow lengths of each pair of oil return slots of the valve sleeve arc bottom buffer tank. 8. The low-noise hydraulic steering gear according to claim 7, characterized in that: one end of the spool has a group of circumferentially spaced oil return slots corresponding to the position of the oil return round slots of the valve sleeve, The oil return groove of the valve core is formed with an arc-bottomed buffer groove whose axial extension length is greater than the flow length of the oil return groove of the valve core. 9 . The low-noise hydraulic steering gear according to claim 8 , wherein the buffer groove extends toward both sides to form a buffer pool whose width is greater than the flow width of the oil return groove hole of the valve core. 10. The low-noise hydraulic steering gear according to any one of claims 1 to 9, characterized in that: the right end of the valve body is equipped with a cycloid pinwheel engagement pair between the partition plate and the rear cover; the valve core A linkage shaft is installed in the middle, and one end of the linkage shaft is respectively connected with the valve sleeve and the valve core through a dial pin and an elastic member to form a rotary valve flow distribution mechanism that cooperates with the flow channel of the valve body.