DE102008030748A1 - Lifting magnet arrangement for use as drive for actuating e.g. hydraulic valve, has pole tubing body radially recoiled at external side in area of transition section, such that supporting ring is provided in circular groove - Google Patents

Abstract

The arrangement has a bush-shaped pole tubing body (5), which is axially divided into a pole section, a transition section and a tubing section. An armature is movably guided into the pole tubing body in an axial direction. The transition section exhibits a smaller wall thickness than the tubing section. The pole tubing body is radially recoiled at the external side in the area of the transition section, such that a circular groove is formed, and a supporting ring is provided in the circular groove. The supporting ring possesses diagonal front surfaces. An independent claim is also included for a method for producing a lifting magnet arrangement.

Description

The The invention relates to a solenoid assembly according to Preamble of claim 1 and a method for producing such a solenoid assembly.

The generic Hubmagnetanordnung is often as a drive for the actuation of hydraulic or pneumatic Valves used in fluid technology.

Actuating solenoids for fluid technology are usually modular and have a liquid-tight pole tube, with the exception of a passage opening for the plunger, in which the armature is movably guided. On the pole tube, a bobbin is mounted. Such an arrangement describes z. B. the DE 10 2006 014 020 A1 ,

in the Polrohr is at the transition from the pole section, against the the armature is energized when energizing the coil, to the pipe section, which together with the coil housing usually forming a yoke, a discontinuity in the magnetic flux provided magnetic field lines in the working air gap between pole and anchor. The discontinuity becomes z. By using a non-magnetic material for bonding of the pole section and the pipe section - these consist made of magnetic material - generated.

Just When switching valves are used as simple as possible Solenoids. An easier way to create a such discontinuity in the pole tube is the reduction the material thickness in the area of the transition. in this connection one takes in favor of the easier production of the pole tube one magnetic tributary through the transition area in purchase. These pile tubes are also called thin-rolled pile tubes, because the reduction in material thickness is more common Way is achieved by twisting. Especially with pressure-loaded Pole tubes may be the material thickness in the transition section do not fall short of certain limits. However, this requires a - im Compared to the usable guided through the working air gap magnetic flux - considerable tributary.

The The present invention provides an improved solenoid assembly. In the transition section between the pole section and the Pipe section of a pole tube body is a groove for reducing the material thickness provided. In the groove is a support ring available.

On this way, the material thickness at high pressure resistance of the pole tube body reduced in the transition section and thus the unusable tributary be restricted. The support ring reinforces the transition section mainly against radial and tangential stresses, according to the boiler formula at a pressure load the conventional limit at the Specify choice of material thickness. According to the The present invention may be the design of the material thickness now based on the lower axial stresses. By compared to conventional pile tubes reduced wall thickness of the magnetic material in the transition region is the reduced magnetic shunt and the efficiency or the Magnetic force are significantly higher.

The The invention further provides an advantageous manufacturing method in which a ring body by forming into a pole tube body formed groove is introduced. The forming process can be flat, play-free concern of the support ring be achieved at the bottom of the groove and the transition section thus optimally supported against radial and tangential expansion become.

advantageous Embodiments of the present invention are defined in the subclaims specified.

According to one preferred embodiment of the present invention is the support ring flat at the bottom of the circumferential groove. This will be a optimal support of the pole tube body in the transition section achieved against radial and tangential stresses. Preferably fills while the support ring, the groove completely.

If the groove has inclined sidewalls, the occurrence of stray fields outside the pole tube reduced.

Preferably the support ring is non-interrupting in the direction of rotation educated. This leads to a high mechanical stability of the support ring.

According to one Particularly preferred embodiment of the pole tube body made of a magnetic material, while the support ring made of a non-magnetic material. This allows it too in one-piece or in a homogeneous magnetic Material formed pole tubes the discontinuity of Magnetic flow in the transition region strong out.

If a transition from the bottom of the groove into the sidewalls Rounded, the material of the support ring can be reliable be incorporated seamlessly into the groove.

According to a further embodiment can at the transition from the groove in the outer surface of the pole portion and the transition from the groove in the Each outer surface of the pipe section may be formed a further annular groove, and the support ring may engage in these annular grooves. As a result, an axial entanglement between the pole portion and the pipe section is made and it can axial stresses via the transition section are received by the support ring.

A for the further processing favorable external contour of the pole tube is achieved when the outer surface the support ring flush with the outer surface of the pole section and the pipe section.

preferred Method for introducing the support ring, which by Forming of the ring body arises, include a rotary swaging method, a Rolling, hot forming or rolling. In these procedures can a play-free concern of the support ring on the groove bottom be achieved. In addition, the slow incremental forming process ensures for a slight tendency to spring back of the Ring body and for a substantially plastic Forming.

According to one Particularly preferred embodiment includes the forming of the ring body a electromagnetic pulse shaping method, in particular an electromagnetic Pulse welding. By this method, the ring body with very short processing time and only expresses low tendency to spring back plastically in the groove as Inserted support ring. The support ring is located u. a. free from play due to the high forming force available with this method and flat on the groove walls and groove bottom.

Preferably is a volume of the ring body dimensioned so that the ring body in the molded state, the groove completely fills.

The mechanical loading of the pole tube body, in particular in axial direction is low in the forming process when the ring body has a smaller axial extent than the groove, so that the ring body can expand axially during forming.

According to one Particularly preferred embodiment, the groove in the transition section formed by swaging. As a result, the pole tube body In the transition section strongly reshaped and thereby the material solidified. In the case of pressure application particularly loaded transition section the pole tube body can therefore high mechanical stresses take up. In addition, the deformation deteriorates the magnetic flux conductivity the transition section, so that the desired Discontinuity is more pronounced.

alternative the groove can be formed during the forming of the ring body, in which the ring body in the pole tube body or is formed in a semi-finished product of the pole tube body.

following For example, the present invention and its advantages are incorporated by reference to the embodiments illustrated in the figures explained in more detail.

1 shows a Hubmagnetanordnung according to the present invention with a valve housing attached to a pole tube, a seated on the pole tube bobbin and a housing enclosing this,

2a shows a Polrohrgrundkörper according to a first embodiment of the present invention, which has a groove in which the wall thickness of the pipe wall is reduced in a transition portion of the pole portion in the pipe section,

2 B represents a ring body, which is similar to the contour of said groove, and

2c shows the Polrohrgrundkörper the 2a After the ring body has been molded into the groove.

3a shows a Polrohrgrundkörper according to a second embodiment of the present invention, which has additional, a main groove axially surrounding annular grooves,

3b shows an annular body, which is provided on the inside with projections which are adapted to the contour of the main groove and the surrounding annular grooves, and

3c shows the Polrohrgrundkörper the 3a after the ring body according to 3b was formed in the grooves.

The 1 shows the typical structure of a solenoid 1 , as it is used to actuate switching valves of fluid technology. On a valve housing 3 is a pole tube 5 of the solenoid 1 screwed into the valve bore. On the pole tube 5 is a magnetic coil 7 attached. The magnetic coil 7 is by means of a mother 9 on the pole tube 5 secured.

The structure and essential for the invention manufacturing steps of the pole tube 5 according to a first embodiment illustrate the 2a . 2 B and 2c , A Polrohrgrundkörper 11 is made of a ferromagnetic steel, z. B. from a bar stock by machining in the in 2a provided form.

The pole tube body 11 is divided axially into a pole section 12 , a transitional section 14 and a pipe section 16 , The overall can-like shape of the Polrohrgrundkörpers 11 allows insertion of an anchor (not shown) into a central bore 18 , The hole 18 is at her the pole section 12 remote end at the opening of the pipe section 16 later with a closure piece - also called stroke limitation - (not shown), which at the same time a thread for fastening the nut 9 wearing.

Through the pole section 12 leads a channel 20 in which a plunger for transmitting the armature movement on a valve piston is receiving and at the same time the compensation of pressure medium between the valve housing 3 and the pole tube interior allowed.

At the transition section 14 is the wall thickness between the lateral surface of the pole tube 5 and the hole 18 by an outer radial circumferential groove 22 reduced. The wall thickness can be in the range of Nutgrunds z. B. less than half the wall thickness in the pipe section 16 amount to the magnetic flux through the transition section 14 to restrict as much as possible. The groove 22 is trapezoidal in cross section. The transition from the groove bottom of the groove 22 in the oblique to the central axis of the pole tube 5 Employed groove walls can be slightly rounded. The groove 22 is made by turning.

Alternatively, the groove 22 by swaging in the Polrohrgrundkörper 11 be introduced. Due to the high degree of deformation when swaging the groove 22 The material is solidified in a desirable manner cold, so that alone thereby already a higher compressive strength of the pole tube 5 can be achieved. In addition, the round kneading of the groove deteriorates 22 the magnetic flux conductivity in the transition section 14 so that the magnetic tributary flow through the transition section 14 is reduced. As a further alternative, a rolling of the groove is possible.

Next is a ring body 24 , as in 2 B presented, provided. The ring body 24 consists of a material with a high modulus of elasticity and high strength. It must be made of non-magnetic - neither ferromagnetic nor ferrimagnetic - material. Suitable materials are austenitic steel, copper alloys or aluminum alloys. The ring body 24 is designed as a trapezoidal ring. He has an inner diameter, which is a pushing on the Polrohrgrundkörper 11 allowed from the Polabschnittseite or from the pipe section side. At the same time, the inner diameter of the annular body 24 as narrow as possible, so that with the Polrohrgrundkörper 11 a clearance is formed. The material volume of the ring body 24 corresponds to the volume of the groove 22 , The angles in which the faces of the ring body 24 are employed with respect to the central axis, have the same amount for both end faces. The angles correspond approximately to the angles of incidence of the groove walls of the groove 22 , Opposite the groove 22 is the ring body 24 shortened.

The ring body 24 gets over the groove 22 arranged and by a joining process in the groove 22 brought in. The 2c shows the Polrohrgrundkörper 11 with in the groove 22 introduced ring body 24 who in this state the support ring 24 ' forms. When joining the radial expansion of the ring body 24 reduces as the axial extent increases.

The support ring 24 ' is free of play on the groove base and on the groove walls of the groove 22 at. He is radially trained interruption-free. The support ring 24 ' takes at the transition section 14 radial and tangential stresses on and supports so in the groove 22 very thin wall to the hole 18 from. This allows a smaller wall thickness in the transition area 14 and thereby low magnetic losses with sufficient compressive strength. With the same wall thickness, the compressive strength of the pole tube 5 increased compared to conventional pole tubes.

For introducing the ring body 24 in the groove 22 the method of electromagnetic pulse forming is used. In this case, the Polrohrgrundkörper 11 with the over the groove 22 deferred ring body 24 introduced into a machining coil. The hole 18 is possibly supported on the inside by a mandrel. The hole 18 However, it can only be done after joining the ring body 24 be executed.

On the machining coil, a strong current pulse is given by a capacitor discharge. Through one in the ring body 24 induced eddy current undergoes this an axially inward force. As a result, the ring body sets 24 full surface, radial backlash-free and possibly also axially backlash-free and springback-free as a support ring 24 ' to the groove bottom and the groove walls of the groove 22 at. The exercise of force and the forming process in this process are almost abrupt and non-contact. This results in the mentioned non-springing deformation of the annular body 24 , a very short processing time in seconds and an extremely low thermal load of the ring body 24 ,

Alternatively to the electromagnetic pulse forming the ring body 24 also by swaging into the groove 22 be introduced. The forming takes place in small steps, whereby the ring body wrinkle-free and radial backlash-free and axially play in the groove 22 is formed.

In addition, it is possible the ring body 24 in the Polrohrgrundkörper 11 or in a rod-shaped semi-finished product as a starting material for the Polrohrgrundkörper 11 mold without first the groove 22 screwed in. By means of the described joining method, the material of the Polrohrgrundkörpers 11 or the corresponding semifinished product during molding of the annular body 24 displaced to the ring body 24 take. The groove 22 forms by itself during the molding process. The plant of the support ring 24 ' at the groove walls and at the groove bottom of the groove thus formed 22 is particularly free of play and intimate. When the ring body 24 is formed in a rod-shaped semi-finished product, no mandrel is needed. After boring out the bore 18 you get a very stable Polrohrgrundkörper 11 with a smooth, high-quality inner peripheral surface.

By the transformation of the ring body 24 this is generally solidified, resulting in increased stability and pressure resistance of the pole tube 5 is achieved. Before molding the support ring 24 ' in the groove 22 can corrosion protection on the ferromagnetic Polrohrgrundkörper 11 be applied. This facilitates the production of a complete corrosion protection layer and increases the reliability. The corrosion protection layer is not affected in particular by the non-contact electromagnetic pulse forming. Subsequent application of a corrosion protection, z. B. a paint on the Polrohrgrundkörper 11 with molded support ring 24 ' is also possible.

A second embodiment will be described with reference to FIG 3a . 3b and 3c described. Differences from the first embodiment exist only in the structural design of the transition section 14 and the ring body 34 opposite the ring body 24 , The basic structure, the method of production and the modifications described can be transferred. Structurally or functionally identical features are assigned the same reference numerals.

The in 3a shown Polrohrgrundkörper 11 owns in the transition area 14 again a radially circumferential groove 22 , The groove 22 has a right angle to the central axis of the Polrohrgrundkörpers 11 aligned groove walls. Alternatively, however, the groove walls can also be set obliquely. The groove 22 is on both sides of two further, radially encircling grooves 30 surrounded, which like the groove 22 in the outer surface of the Polrohrgrundkörpers 11 are introduced. The grooves 22 and 30 can be made by turning, by swaging or by rolling.

The grooves 30 have a smaller depth than the groove 22 , The webs between the grooves 30 and the groove 22 have a lower radial height than the lateral surface of the pipe section 16 or the adjacent pole section 12 ,

In 3b is a ring body 34 shown, for molding in the grooves described 22 and 30 is provided. The ring body 34 has an inner diameter, the sliding on the Polrohrgrundkörper 11 - preferably in the context of a clearance fit - allowed.

On the ring body 34 stand in the inner peripheral surface of a broad center bar 36 and on the front sides in each case the outer webs 38 radially inward. The central pier 36 is further inward than the outer webs 38 , The axial dimensions are such that when the center bar 36 by pushing the ring body 34 on the Polrohrgrundkörper 11 over the groove 22 is arranged, the outer bars 38 over the grooves 30 to come to rest.

After pushing the ring body 34 on the Polrohrgrundkörper 11 becomes the ring body 34 into the grooves 30 and 22 inserted, like 3c shows to the support ring 34 ' to build. The support ring 34 ' it also spans the webs between the grooves 22 and 30 , As a joining method, the method already described in the first embodiment, electromagnetic pulse forming and rotary kneading come into question.

A special feature of the second embodiment is that the support ring 34 ' by its positive engagement in the grooves 30 axial tensile stresses, which upon pressurization of the pole tube 5 in the groove 22 of the transitional section 14 prevail, absorbs. Such tensile stresses are caused by the support ring 34 ' in the pole section 12 and the pipe section 16 where one compared to the groove 22 greater wall thickness is available, derived.

The Hubmagnetanordnung invention comprises a sleeve-shaped pole tube body, which axially into a pole section, a transition section and a pipe section, and an anchor, which in the pole tube guided in the axial direction movable. The transition section has a smaller wall thickness than the pipe section. In the area of the transition section, the pole tube body jumps radially back on the outside, leaving a circumferential groove is formed. In the circumferential groove a support ring is provided.

In this way, the material thickness can be reduced at high pressure resistance of the pole tube body in the transition section and thus the unusable tributary be restricted. The support ring reinforces the transition section mainly against radial and tangential stresses which, according to the boiler formula, give the conventional limit in the choice of material thickness under a compressive load. According to the present invention, the design of the material thickness can now be based on the lower axial stresses. Due to the reduced wall thickness of the magnetic material in the transition region compared with conventional pile tubes, the magnetic bypass is reduced and the efficiency and the magnetic force are significantly higher.

1

solenoid

3

valve housing

5

pole tube

7

solenoid

9

mother

11

Polrohrgrundkörper

12

pole section

14

Transition section

16

pipe section

18

drilling

20

channel

22

groove

24

ring body

24 '

support ring

30

groove

34

ring body

34 '

support ring

36

center web

38

outer webs

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102006014020 A1 [0003]

Claims (17)

Hubmagnetanordnung, comprising a sleeve-shaped pole tube body ( 5 . 11 ), which axially into a pole section ( 12 ), a transitional section ( 14 ) and a pipe section ( 16 ), and an armature, which in the pole tube body ( 5 . 11 ) is movably guided in the axial direction, wherein the transition section ( 14 ) a smaller wall thickness than the pipe section ( 16 ), characterized in that in the region of the transitional section ( 14 ) the pole tube body ( 11 ) jumps back radially on the outside, so that a circumferential groove ( 22 ) is formed, and that in the circumferential groove ( 22 ) a support ring ( 24 ' . 34 ' ) is provided. Hubmagnetanordnung according to claim 1, characterized in that the support ring ( 24 ' . 34 ' ) at the bottom of the circumferential groove ( 22 ) lies flat. Hubmagnetanordnung according to claim 1 or 2, characterized in that the support ring ( 24 ' . 34 ' ) the groove ( 22 ) completely. Hubmagnetanordnung according to one of claims 1 to 3, characterized in that the groove ( 22 ) has inclined side walls. Hubmagnetanordnung according to one of claims 1 to 4, characterized in that the support ring ( 24 ' ) has inclined end faces. Hubmagnetanordnung according to one of claims 1 to 5, characterized in that the support ring ( 24 ' ) is designed to be interruption-free in the direction of rotation. Hubmagnetanordnung according to one of claims 1 to 6, characterized in that the pole tube body ( 11 ) consists of a magnetic material and that the support ring ( 24 ' . 34 ' ) consists of a non-magnetic material. Hubmagnetanordnung according to one of claims 1 to 7, characterized in that a transition from the bottom of the groove ( 22 ) is rounded in the side walls. Hubmagnetanordnung according to one of claims 1 to 8, characterized in that at the transition from the groove ( 22 ) in the outer surface of the pole section ( 12 ) and the transition from the groove ( 22 ) in the outer surface of the pipe section ( 16 ) each have a further annular groove ( 30 ) are formed and that the support ring ( 34 ' ) in these annular grooves ( 30 ) intervenes. Hubmagnetanordnung according to one of claims 1 to 9, characterized in that the outer surface of the support ring ( 24 ' . 34 ' ) flush with the outer surface of the pole section ( 12 ) and the pipe section ( 16 ). Method for producing a lifting magnet arrangement according to one of Claims 1 to 10, which comprises providing the pole tube body ( 11 ), Providing an annular body ( 24 . 34 ), whose inner diameter is greater than an outer diameter of the pipe section ( 16 ) or pole section ( 12 ), Arranging the ring body ( 24 . 34 ) above the pole tube body ( 11 ) and forming the ring body ( 24 . 34 ), so that this in a pole tube body ( 11 ) formed groove ( 22 ) is introduced. A method according to claim 11, characterized in that the forming of the annular body ( 24 . 34 ) comprises at least one rotary swaging, rolling, hot working or curling. A method according to claim 11 or 12, characterized in that the forming of the annular body ( 24 . 34 ) comprises an electromagnetic pulse shaping method, in particular an electromagnetic pulse joining. Method according to one of claims 11 to 13, characterized in that a volume of the annular body ( 24 . 34 ) is dimensioned so that the annular body in the molded state ( 24 ' . 34 ' ) the groove ( 22 ) completely. Method according to one of claims 11 to 14, characterized in that the annular body ( 24 ) or a bridge ( 36 ) of the ring body ( 34 ) has a smaller axial extent than the groove (FIG. 22 ), so that the annular body ( 24 ) or the bridge ( 36 ) can expand axially during forming. Method according to one of claims 11 to 15, characterized in that the provision of the pole tube body ( 11 ) it includes the groove ( 22 ) in the transition section by swaging. Method according to one of claims 11 to 15, characterized in that the groove ( 22 ) during forming of the ring body ( 24 . 34 ) is formed, in which the annular body ( 22 . 34 ) in the pole tube body ( 11 ) or in a semi-finished product of the pole tube body ( 11 ) is formed.