This application claims priority under 35 U.S.C. § 119 to patent application nos. DE 10 2019 207 949.0, filed on May 29, 2019 in Germany, and DE 10 2020 203 953.4, filed on Mar. 26, 2020 in Germany, the disclosures of which are incorporated herein by reference in their entirety.
The disclosure relates to 2/2 and 3/3 directional insert valves, and to a method for the production thereof.
The applicant's data sheets RD 21010 (edition 2017-05), RD 21040/2017-05, and RD 21050/2003-02 have disclosed 2/2 directional insert valves which have a bushing which is inserted into an insert bore of a valve housing. In this case, an annular duct is formed in the insert bore so as to be interposed with respect to the bushing. A duct is arranged in the valve housing radially with respect to the bushing and opens into the annular duct. In the region of said annular duct, four or more circular holes or passage cutouts are provided, and separated from one another by webs, in the bushing. A movable closing body is received in the interior of the bushing. If said moving body is moved or pushed away from the passage cutouts, the passage cutouts are opened and a pressure medium connection between the annular duct and a face-side opening of the bushing is opened up.
A disadvantage of 2/2 directional insert valves of said type is the throughflow resistance thereof, which arises as a result of the relatively small passage cutouts and in particular as a result of the webs which are arranged between the passage cutouts.
By contrast, it is the object of the disclosure to provide a 2/2 and a 3/3 directional insert valve having a bushing and passage cutouts formed therein, wherein the throughflow resistance of the insert valve is reduced.
Said object is achieved by a 2/2 directional insert valve, or a 3/3 directional insert valve, having the features of Patent claim 1, and by a method for the production thereof having the features of Patent claim 14.
Further advantageous configurations of the disclosure are described in the dependent patent claims.
The claimed 2/2 and 3/3 directional insert valves have a bushing in which a closing body is guided. Passage cutouts are arranged in a circumferential direction of the bushing, preferably on a circular path. According to the disclosure, the passage cutouts are elongate holes which are larger (that is to say longer) in the circumferential direction of the bushing than in an axial direction of the bushing. In this way, a radial opening surface of the passage cutouts is maximized. In this way, the throughflow resistance of the passage cutouts and thus of the insert valve is reduced.
One exemplary embodiment involves a 3/3 directional insert valve whose closing body is a control slide. The bushing is then provided with a second group of passage cutouts, which are axially spaced apart from the first-mentioned passage cutouts. The passage cutouts of the second group are likewise arranged distributed in a circumferential direction of the bushing, preferably on a circular path. According to the disclosure, the passage cutouts of the second group are then also elongate holes which are larger in the circumferential direction of the bushing than in the axial direction of the bushing. In this way, a radial opening surface is maximized for the passage cutouts of the second group too. In this way, the throughflow resistance of the passage cutouts of the second group and thus of the insert valve is reduced for throughflow of the second group of elongate holes too.
In one refinement of the 3/3 directional insert valve, a first group of control cutouts and, axially spaced apart therefrom, a second group of control cutouts are arranged distributed on the control slide and, at least sectionally, are able to be brought into overlap with the elongate holes of the bushing. The control cutouts are particularly preferably likewise elongate holes which are larger in the circumferential direction of the control slide than in an axial direction of the control slide. In this way, the throughflow resistance of the passage cutouts of the second group and thus of the insert valve is reduced for throughflow of the second group of elongate holes too.
It is normally the case that webs remain between the elongate holes, which webs, according to one refinement of the disclosure, are reinforced in a radial direction in comparison with a guide region of the bushing that is closed over the full circumference. The guide region surrounds the closing body. The radial reinforcement is formed by way of an increase in the radial material thickness of the webs toward the outside in the direction of an annular duct. It is consequently possible to compensate for possible weakening of the webs as a result of the enlargement according to the disclosure of the passage cutouts.
In a preferred application of the disclosure, the insert valve is a seat valve, wherein the bushing has on the inner circumference a valve seat for the closing body. Advantageously, provision is then made for a reduction in the inner diameter of the bushing between the valve seat and a face-side opening of the bushing. The reduction in the inner diameter is to be understood in relation to the fully circumferential guide region of the bushing, in which guide region the closing body is guided. A thickening for increasing the strength in comparison with the fully circumferential guide region is consequently achieved.
If, as viewed in a circumferential direction, the webs extend over at most 25%, particularly preferably over at most 20%, of the outer circumference of the bushing, an optimal balance between strength of the bushing, on the one hand, and reduced throughflow resistance, on the other hand, is achieved.
In a preferred application of the disclosure, the bushing has on its outer circumference a radial step, or a further bushing is provided and forms a radial step with the bushing. By way of the radial step, an annular duct, at the face sides, is able to be delimited or is delimited in the inserted state.
If the step has a greater radial extent than the wall thickness of the fully circumferential guide region of the bushing, in which guide region the closing body is guided, the annular duct also has reduced throughflow resistance.
The annular duct has particularly reduced throughflow resistance if the step has a greater radial extent than the radial extent (thickness) of the reinforced webs.
In one exemplary embodiment of the 2/2 directional valve, two elongate holes are provided, and in another exemplary embodiment, three elongate holes are provided. At the bushing of the 3/3 directional valve, two groups of in each case two or three elongate holes distributed on the circumference may be provided. Consequently, in comparison with the prior art with four, six or even eight passage cutouts, the likelihood is reduced that one of the webs is situated exactly opposite an inflow duct of the valve block, which inflow duct opens from the outside, preferably radially, into the annular duct. If the insert valve according to the disclosure has been inserted into the valve block, in a relatively unfavorable case, only one of the webs is situated opposite the inflow duct, which web is furthermore also designed with a width in the circumferential direction of the bushing that is reduced in comparison with the prior art. Furthermore, there is a greater likelihood that no web is situated opposite the inflow duct, but that one of the elongate holes is situated opposite the inflow duct. Consequently, in all cases, the resistance of the flow from the inflow duct radially through the annular duct into one or at most two of the elongate holes is reduced.
It is particularly preferable if the elongate holes and/or the control cutouts of each group are distributed uniformly in a circumferential direction of the bushing or of the control slide.
On the face side of the bushing or of the further bushing, at least one marking, which simplifies the optimal orientation of the bushing, may be provided. Preferably the marking is introduced as a groove in the bushing directly centrally above the elongate hole.
The method according to the disclosure serves for making the elongate holes in the bushing of the above-described insert valve in a simple manner, and comprises the steps of:
Two exemplary embodiments of the insert valve according to the disclosure are illustrated in the figures.
In the figures:
The insert valve can be flowed through on both sides, that is to say the inflow and outflow ducts may also be swapped around in comparison with the exemplary embodiment described.
The insert valve has an inner bushing 8 and a further bushing 10, which are fastened to one another. Since the further bushing 10 has a greater outer diameter than the inner bushing 8, a radial step 12 is formed on the outside of the insert valve. The radial step 12 delimits at a face side an annular space or annular duct 14, which is furthermore formed between an outer lateral surface of the bushing 8 and the cutout 1 of the valve block 2. The inflow duct 6 opens into the annular duct 14.
In the interior of the bushing 8, a closing body 16 is guided along the longitudinal axis 4. When the closing body 16 is loaded (downwardly in
In the exemplary embodiment shown, the webs 22 take up only 20-25% of the outer circumference of the bushing 8. This consideration holds true for the section plane shown in
In the open position, shown in
Provision is made for a reduction in the inner diameter of the bushing 8 between the valve seat 18 and the face-side opening 24.
Between the elongate holes 20 and that end portion of the bushing 8 which is opposite the face-side opening 24 and to which the further bushing 10 is fastened, the bushing 8 has a fully circumferential guide region 26, via which, substantially, the guidance of the closing body 16 along the longitudinal axis 4 is realized.
When inserting the 2/2 directional insert valve, one of the markings 28 and thus one of the elongate holes 20 of the bushing 8 can then be optimally oriented with respect to the inflow duct 6.
In the interior of the bushing 108, a control slide 116 is guided along the longitudinal axis 4.
Two groups of in each case three elongate holes 20 are provided on the circumference of the bushing 8, which elongate holes are distributed uniformly on the circumference and are separated from one another by a corresponding number of webs 22.
It can furthermore be seen that two groups of in each case four control cutouts 130 are provided on the circumference of the control slide 116, which control cutouts are distributed uniformly on the circumference and are separated from one another by a corresponding number of webs.
In the position of the control slide 116 shown in
Starting at the position of the control slide 116 shown in
What is disclosed is an insert valve having a bushing 8; 108 which has, as a pressure medium passage, holes distributed on the circumference or which has, as pressure medium passages, two groups of holes distributed on the circumference. Via the holes and an interior of the bushing 8; 108, an annular duct 14 at the outer circumference of the bushing 8 is able to be connected to a port 24 on a face side of the bushing 8, or two annular ducts at the outer circumference of the bushing 108 are able to be connected to the port 24 on the face side of the bushing 8. The holes are able to be closed off by a displaceable closing body 16; 116. For the purpose of minimizing the throughflow resistance, the holes, in comparison with the prior art, are enlarged in a circumferential direction and are formed as elongate holes 20.
Number | Date | Country | Kind |
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10 2019 207 949.0 | May 2019 | DE | national |
10 2020 203 953.4 | Mar 2020 | DE | national |