DE2117579A1 - Electromagnet - Google Patents

Description

DIPL-INGl HORST ROSE DIPL-IN & PETER KOSEL PATENT LAWYERS? 1 1 7 £ 7 ct

3353 Bad Ganderehelm, April 8, 1971 P.O. Box 129 HohenhöfenS Telephone: (05382) 2S42

Telegram address: Siedpatent Badgandersheim SW Msk CO. » Ine. ÜRseraAkterr-No. 2556/2

Patent application dated April 8, 1971

G »W. Msk Go., Ine.

2 South Street

Glifton Springs »K.Y. 144-? 2

Y.St.A.
Electromagnet

The invention relates to an electromagnet with an axially displaceable in a tube under the action of a magnetic force arranged armature for operating a device, preferably a Yentils.

A first known type of electromagnet used an electromagnet frame and an armature, both of which are constructed from blanks of magnetic sheet metal riveted together are riveted together. Since such a construction does not relieve the pressure on the inside of a valve to the outside can seal, a Q-ring resting against the solenoid's push pin is used as a dynamic seal. About 5 $ of the power of the electromagnet is lost that the friction of the O-ring on this push pin is overcome must become. This frictional force increases with increasing operating pressure strongly, and in some cases it can be greater than the force of the electromagnet, so that the working pressure must be reduced to a fraction of the operating pressure, so that the electromagnet can actuate the hydraulic valve at all. Furthermore, the sheet metal construction is poor in the able to withstand impact forces! she yields Actuation of a hydraulic valve no seal * and the

tÖ9Ö45 / f t9t

Bank account: Norddwfrch · Landesbank. Branch «Bed Ganefer * h» tn », account number 22.118.970 · Postal checking account: Hannover66715

O-ring seal is a constant source of friction and leakage. Also occur on O-Bing after about 4 million Valve clearances often damage (due to incipient leakage losses) which requires the Q-ring to be replacedj the new O-ring is usually difficult to find to be built in. In addition, such an installation requires that the hydraulic valve is removed and dismantled, when the new O-ring is installed «

A second known type of electromagnet, too which can also be counted as the present invention, gives certain advantages over that discussed above first type. This second type is built around a tube in which a solid anchor is placed in the hydraulic oil. This eliminates the need to use a dynamic O-ring seal and thus eliminates it also the tile parts of this type of seal. However, this has Second type of construction essential parts of the Kach, because usually only relatively small forces can be achieved with it, and furthermore generally a very strong development of heat occurs in it as a result of eddy currents in the massive metal parts of the magnetic circuit, and also as a result from the fact that the electromagnet always requires a relatively high holding current (practically an inrush current) because the non-magnetic pipe lies in the path of the magnetic lines of force and therefore practically an air gap for them represents. Because of the low force available, this second design can only be used to actuate the smallest valves can be used unless a pilot valve is used for actuation of the main valve is used. The usage a pilot valve expensive and complicated but one such arrangement very strong.

It is therefore an object of the invention to provide the aforesaid second type of electromagnet to improve.

109845 / 119t

According to the invention, this is the case with one mentioned at the beginning Electromagnet achieved in that a laminated magnet yoke is provided with a coil window provided therein is which yoke in opposite side walls ever has an opening that a ring coil is arranged in the coil window and is provided with a central opening which is roughly coaxial with the two openings that the tube passes through these two openings and through the central opening extends the ring coil and is provided on its underside with a stop which has an axial recess is provided through which a push pin resting against the armature extends out of the electromagnet, and that the top of the tube is provided with a seal to prevent leakage of liquid. The electromagnet is particularly advantageously designed in such a way that the tube is made of a semi-austenitic material is made, which is treated so that it is magnetically and in two sections in the area of the magnetic yoke a section lying between these two sections is non-magnetic. Such a pipe is easy to manufacture and represents a significant improvement over the known constructions, since the holding current is reduced and thereby the heat losses can be significantly reduced. Such an electromagnet can therefore be a generate much higher force.

It is particularly suitable for lower pressures (a definition of the pressure ranges is given below) Another inventive construction of an electromagnet with one in a tube under the action of a Magnetic force axially displaceable armature for actuating a device, preferably a pressure medium valve or in a system with low pressure medium pressure, which is characterized in that a magnet yoke and a coil arranged in this are provided that the

1 0 9 a U 5/1 1 9 1

-A-

Tube is arranged within the coil and magnet yoke, and that it is completely magnetic and very thin-walled and has high strength. Such a pipe can go through the rivers running parallel to the longitudinal axis in its mantle are relatively easily saturated, while it is for the fluxes radially passing through it represents a low magnetic resistance · This also results a reduction in the holding current and thus a significantly lower thermal load. - The thrust electromagnet (for high and for low pressure) are also characterized by an improved magnetic yoke, an 'improved armature and thrust pin and a particularly favorable range for the ratio of coil length to length of the working gap. The pull electromagnets (for high and for low pressure) use a terminated tube for the armature, as well as improved magnet yokes and improved anchors.

Further details and advantageous developments of the invention emerge from those described below and embodiments shown in the drawing, as well as from the claims.

Show it

1 shows a partial longitudinal section through a thrust electromagnet according to the invention connected to a hydraulic valve,

2 shows a three-dimensional representation of the magnetic yoke of the electromagnet according to FIG. 1,

3 shows a three-dimensional representation of a stop used in the electromagnet according to FIG. 1,

FIG. 4 shows an enlarged cross section through an organ provided on the electromagnet according to FIG. 1 for the preferred one Operation by hand,

1098A5 / 1191

_ 5 -

5 shows a cross section through an inventive Pull electromagnet,

Pig. 6 shows a three-dimensional representation of the magnet yoke of the electromagnet according to FIG.

7 shows a cross section through another train electromagnet according to the invention,

8 shows a three-dimensional representation, partially shown in section, of an anchor according to the invention for the Electromagnet according to Fig, 7, and

9 is a three-dimensional, partially shown in section another embodiment of an inventive Armature, as it can be used, for example, in the electromagnet according to Fig. 7.

For ease of understanding, the following description of the various features is present Invention divided into two main parts, viz

1. Thrust solenoid and
2 «pull electromagnet.

Throughout the description and the claims, the expressions "high pressure" and low pressure ¹ · refer to the pressure of the operating pressure rail in kp / om in a hydraulic valve which is actuated by electromagnets according to the invention. The term "low pressure" is defined as the range between about 0 and about 70 kgf / cm and the term "high pressure" is defined as all pressures above 70 kg / cm, usually from about 70 to 210 kg / cm. In order to have an expedient reference system with regard to the orientation of the electromagnets in the present description and in the claims, the terms "top side" and underside "of an electromagnet are defined as follows

109845/1191

Fig. 5 shows a vertically arranged electromagnet 100 with an upper side 1 and a lower side 2. In the same way, the electromagnet 12 according to FIG. 1 has a Upper side 3 and a lower side 4. In the spring case, the pull pin 168 or the push pin 24 extends from the lower side the electromagnet off; a valve, e.g. the valve "10 according to Fig. 1, is therefore attached to the underside of the electromagnet. - The selected terms" underside " and "top" are naturally arbitrary, since the electromagnets according to the invention have any desired position can. - The term "normal position" of the armature is defined as its non-excited position, in contrast to the position it assumes after the electromagnet has been energized, thereby causing the armature to move moved through the working gap into its "excited" position.

Thrust electromagnet High pressure thrust electromagnet

1 to 4 show a preferred embodiment of an alternating current actuable according to the invention Hoohdruok thrust electromagnet 12.

Before describing the details of the electromagnet a brief description of an overall view of a particular is intended for ease of understanding Application of the electromagnet 12 are given. Fig. 1 shows a hydraulic valve 10, which on two opposite Pages connected to a pair of identical high-pressure thrust electromagnets e 12 and 14, which according to the invention are trained. The valve 10 forms part of a (not shown) hydraulic control, and actuation of valve 10 by solenoid 12 or solenoid 14 results in a particular desired one Event in the hydraulic control circuit. If, for example, the

109B4S / 1191

When solenoid 12 is energized, it causes a slide 13 in valve 10 to move to the right (with reference to FIG. 1), establishes a hydraulic connection between certain passages (cf. passage 15) of valve 10, and the hydraulic connection between certain other passages in valve 10 interrupts. The passages are connected to hydraulic lines (not shown) of the hydraulic control via connections. The valve 10, the hydraulic control (not shown) and the connecting means (not shown) between the valve 10 and the hydraulic control are all known parts which do not form part of the present invention and therefore need not be described in further detail here _e

The electromagnet 12 according to FIG. 1 has a magnet yoke 16 (shown in detail in FIG. 2) which forms a window 17 for an annular coil 18 arranged in it, as well as a hollow cylindrical tube 20 for the anchor that defines an anchor recess 21 and lies within the magnet yoke 16 and the coil 18. A cylindrical armature 22 is arranged in armature recess 21 and axially displaceable therein. A push pin 24 rests against the armature 22 and is separated from it. It is arranged displaceably in an axial recess 26 of a stop 28, the latter in detail in 3 and is connected to the tube 20. The stop 28 limits the travel of the armature 22 when the electromagnet 12 is energized. The armature 22 is shown in FIG. In a non-excited or "normal position". When the electromagnet 12 is excited, the armature 22 moves into contact with the stop 28. One that can be actuated by hand Control device 30 for the preferred arbitrary displacement of the armature 22 is on the left (with reference to FIG. 1)

10 9 8 4 5/1191

Tube 20 attached. Preferably, the various components of the electromagnet are comprised of a layer 32 surrounded by epoxy resin.

Fig. 2 shows the magnet yoke 16, which is used as a Wickelbandkejrn and has a substantially rectangular window 17 for receiving the coil 18. That MagnetJoch 16 has two circular openings 36 and 37, one in each of its two opposite long sides 38 and 39 j the openings 36 and 37 are used for receiving of the tube 20, as shown in FIG. Furthermore, the magnet hole 16 is according to a feature of the present invention Invention provided with a slot 40 in order to interrupt V, denoted by 42, and thereby vortex current paths to reduce the eddy currents which otherwise contribute to the heating of the magnet yoke 16 made of metal. The slot 40 does not interfere with the desired paths of the magnetic fields, which are indicated by arrows 44.

The slot 40 can also be arranged on the other side of the openings 36 and 37 (with reference to FIG. 2) and, as an alternative, it can also be provided on both sides of the openings 36 and 37 if desired, but then the two halves of the Magnet yoke 16 are held together mechanically.

The construction and shape of the coil 18 are known. It has two connecting wires 46, which in a known manner are led out of the electromagnet 12 in order to be able to connect it to an electrical voltage source. The coil 18 may be encapsulated in a protective cover 19 made of epoxy resin.

The tube 20 seals the coil 18 against the liquid in the electromagnet 12 and also forms the cylindrical one Armature recess 21 between the manually operated control device 30 and the stop 28. The tube

109845/1191

20 is made sufficiently thick to achieve the desired operating pressure of the liquid in the armature recess 21 to be able to resist. According to the invention, the tube 20 is preferably made of semi-austenitic steel, e.g. Steel known in the USA under the type designation "17-7 P.H. stainless steel" (P.H. = .precipitation hardening = precipitation hardening). The tube 20 is located in its axial sections 54 and 56 (Fig. 1) in its magnetic (Martenaitic) state to the To oppose the magnetic field as little resistance as possible if it is in these sections 54 and 56 the Wall of Rohree 20 penetrates radially. On the other hand, the tube 20 is located in its axial section 58 (Fig. 1) in its non-magnetic (austenitic) state) that for the magnetic field which tries to penetrate the section 58 of the tube 20 axially, the greatest possible Oppose resistance. The construction forces the largest possible part of the magnetic field to to penetrate a work area 50 and so a usable one Generate electromagnetic force. Various methods of selectively treating different sections of semi-austenitic resistance Steels are known and such methods can be used in the pipe 20 of the present invention to produce which sections 54 and 56 in the magnetic state uiJLd a section 58 in the non-magnetic state having.

Haibauetenitisehe alloys are austenitic (non-magnetic *) structures in the solution-annealed condition (annealed condition). The transformation of austenite into Martial (magnetic) structures can be created by a Heat treatment can be achieved, which the austenite for • Prepared for a transformation when it cools down. Cold working (about $ 60 reduction) also gives the transformation

109845/1191

of austenite in martensito. The tube 20 according to the invention can be made by starting with the tube in the annealed state. The martensitic transformation is achieved of the entire pipe through a heat treatment in the furnace. A section of the tube is then selectively annealed. An alternative is to start with a cold-worked tube that is already in the martensitic state, and selectively anneal a section.

The tube 20 according to the invention is significantly less expensive than tubes which are made up of two separate pieces, namely one magnetic and one non-magnetic piece, are butt welded together.

The armature or magnetic core 22 is a cylindrical body with a slot 60 (the section according to FIG. 1 runs through the slot 60), this slot 60 is relatively narrow, e.g. «smaller than 3» 2 mm wide, and it lies in a plane parallel to the Aohse of the electromagnet 12. The Slot 60 reduces the eddy currents in armature 22 «It also contributes to better transfer of the liquid from one End of the recess 21 to the other end during operation at. An underside 62 of the slot 60 extends at an angle to the longitudinal axis of the electromagnet, like that. is shown in Fig. 1 in order to reduce the eddy currents as much as possible, but still an uninterrupted one To ensure contact surface for the push pin 24, ao that the transmission of force d & s electromagnet on the push pin 24 is not affected

The Sohubstift 24 is preferably made of a material manufactured under the trademark "TANTÜNÖ G" is sold and which is composed as follows:

10 9 8 4 5/1191

cobalt 45 ... 5Of ₀ chrome 27 ... $ 32 tungsten 14 ... $ 19 carbon 2 ... tfo Tantalum or niobium 2 ... 11 * manganese 1 ... $ 3 iron 2 ... 5 <£

The push pin 24 made from "TANTUNG G" has a Rockwell hardness of about 60 and is non-magnetic. Such hardness is desirable so that the ends of the push pin 24 do not expand due to loading (impacts, etc.) or even burst open. The magnetic flux contained in the prior art steel magnetic pusher pins flows, results in an electromagnet power loss of about 10%. The push pin 24 according to the invention is omitted this loss, while the hardness of the pen remains the same as that of a magnetic pen.

Details of the stop 28 are shown in FIG. This has a cylindrical body 70 with a on its underside arranged retaining flange 72 on} the body 70 is entirely from the axial recess 26 for receiving of the push pin 24 penetrated. The stop 28 is also parallel to the longitudinal axis with a relatively narrow slot 74 of the electromagnet 12 is provided in order to reduce the eddy currents in the stop 28. The slot 74 extends duroh that part of the stop 28 which is arranged axially within the magnet joinder 16 and the coil window 17 is. The upper side 76 of the stop 28 is provided with an annular groove 78 for receiving a shielding coil 79 (cf. Pig. 1), the purpose of which is well known to the person skilled in the art is known (prevent sticking).

109845/1191

Fig. 4 shows a longitudinal section on an enlarged scale by the manually operable control device 30. It has a molded piece 80 which is fastened to the pipe 20 and is provided with a cylindrical cavity 82 in which a button 84 between two snap rings 86 and 88 is arranged to be axially displaceable. The button 84 is used for arbitrary manual actuation of the electromagnet 12 and thus of the valve 10. The molded piece 80 is also provided with an axial recess 90 for receiving a provided with the button 84 connected plunger 92. The cavity 82 (and thus the outside of the electromagnet 12) are against the hydraulic pressure inside the electromagnet 12 and the valve 10 are sealed by means of an O-ring seal 94, which is in contact with an O-ring holder 96 is held against the plunger 92. The holder 96 is held in place by the snap ring 88. An exit of pressure medium from the valve 10 via the electromagnet 12 is thus prevented by the O-Ring'94.

When button 84 is pushed in, plunger 92 pushes armature 22 and push pin 26 to the right (with reference to FIG. 1) in order to actuate the valve 10.

It has been found that the ratio between the length X (FIG. 1) of the coil 18 and the length Y of the working gap 50 is preferably in the range between 3 and 6 target. If the ratio is significantly smaller than 3 », the stray fields increase so much that the force of the Electromagnet is noticeably reduced. If the ratio is significantly greater than 6, the losses in the magnetic core increase very strong and cause a warming, which more than compensates for the small decrease in the stray fields.

Using the preferred art construction described above of a high-pressure thrust electromagnet, one achieves significant advantages, as already mentioned at the beginning

109845/1191

became. Because the O-ring seal used in the known valves on the push pin is omitted, which in these valves is used to seal the electromagnet against the valve, the loss of power of the • Avoid using electromagnets caused by the friction of the O-rings are created on the push pin. Furthermore, the use of a laminated magnetic yoke results in a selective one magnetized and demagnetized tube for the armature, a slotted magnet yoke, a semi-austenitic one Tube for the anchor, a push pin from "TANTUNG G" and the use of a preferred Ratio of coil length to working gap a significantly higher force and significantly lower heat losses, i.e. a lower operating temperature.

Niederdruok Sohub electromagnet

The low-pressure thrust electromagnet according to the invention is constructed in the same way as the high-pressure thrust electromagnet 12, which has been described in detail above, with the exception that the Niederdruok-Sohub electromagnet has a tube is used for the anchor (corresponding to the tube 20), which is very thin-walled and completely magnetic. This pipe is chosen about half as thick as that Tube 20 in the high pressure version. For example, you choose the wall thickness for a pipe diameter of around 19 mm of the tube 20 'in the case of the high-pressure electromagnet to about 0.71 mm, with the low-pressure electromagnet, on the other hand, it is 0.36 mm. In the preferred construction, the tube is for the anchor Heat treated to a very high strength to allow the use of a very thin wall thickness. Since the thin-walled tube is made of magnetic material, it results in a relatively low magnetic resistance for a magnetic flux, which radially at points

109845/1191

speaking the sections 54 and 56 of Fig. 1 goes through the pipe wall. On the other hand, it has the same thin wall thickness a restriction on the size of the flow axially at a point corresponding to section 58 of FIG. going through the pipe. This thin wall thickness also has the effect that the cross-section in which eddy currents flow in the pipe can be reduced. - The tube is preferably made of a material with a low maximum magnetisohen Permeability of about 200, so that preferably the tube at the section 58 of FIG. 1 corresponding Place in the saturation and thereby the magnetic flux is further reduced at this point. The wall thickness the pipe is so thin that the reduced permeability at those corresponding to sections 54 and 56 of FIG. 1 Make the radial magnetic flux not significantly hindered * The use of the invention thin tube enables the holding current to be reduced of the electromagnet to a value which itself is below that which can be achieved with a pipe that is made of a magnetic and a non-magnetic part, and it enables a higher force to be obtained than with a one-piece non-magnetic tube

The manufacturing costs of the thin-walled tube are significantly lower than those of the assembled tube, and they compare favorably with the cost of a one-piece, non-magnetic tube.

It has been found to be a slight deterioration the efficiency by having some magnetic lines of force linearly through the middle section of the tube (corresponding to section 58 in the case of tube 20 according to FIG. 1), more than is compensated for by the increased efficiency due to the fact that the magnetic resistance for the outer sections (corresponding to the sections 54 and 56 of Fig. 1) of the pipe

1 09845/1191

penetrating magnetic field becomes very small. The use of the thin-walled according to the invention, continuous Magnetic tube thus gives a better efficiency than the use of a thick, continuously non-magnetic tube according to the prior art.

Train electromagnet High-pressure pull electromagnet

In Figures 5 and 6 there is a preferred high pressure pull solenoid 100 shown according to the invention. 7 and 8 show another high- Pull solenoid 150, and Fig. 9 shows one modified armature 194. It should be noted that by means of the one shown in FIGS Constructions, the stop for the armature required according to the state of the art could be omitted »This is why very desirable because the stop probably caused the greatest electrical losses in the electromagnet because it had to seal the pressure in the hydraulic system and therefore not laminated or even only effectively with slots could be provided.

The pull electromagnet 100 according to FIG. 5 has the following parts: A magnet yoke defining a coil window 104 102, a ring coil 106 of known construction arranged in this window 104, and a hollow, cylindrical one Tube 108 for the armature with a recess 110 arranged centrally in the magnet yoke 1-02 and the coil 106 for the armature, the tube 108 extending outside the magnet yoke 102 through a circular opening 112 in a laminated side plate 114 of the yoke 102 extends. The coil 106 is pigtailed in the usual manner 116 provided. A solid, cylindrical, non-laminated anchor 118 is arranged in recess 110 in tube 108

109845/1 191

and axially displaceable from its "normal position ¹¹ " (shown in FIG. 9) to its excited position, in which it is in contact with a cap 136. The armature 1.18 is provided with a thin slot 120 which extends at least through the The slot 120 is parallel to the longitudinal axis of the armature 118 and extends at least partially through it To create a fluid passage which allows the required flow between a valve (not shown) to which the electromagnet 100 is connected and a working gap 122 in the recess 110. The armature 118 does not require a separate groove for this purpose connected to the armature 118, and when the electromagnet 100 is energized, the armature 118 moves through the working gap 122 n ach up (based on FIG. 5) and thus actuates a pressure medium valve (not shown) which is connected to the tension pin 124.

Fig. 6 shows an exploded view of the magnet hole 102, which is formed from two separate sheet metal parts. One part is a main part 126 which is shaped like a capital E and the other part is the straight, elongated side plate 114. The part 126 and the side plate 114 are constructed as a vertical stack of thin flat sheet metal sections 128 and 130, respectively. After the coil 106 has been placed in the recess 104 of the part 126, the plate 112 is attached to the part A4 ^ - , for example by using a frame made of parts with a U-shaped cross-section, or by resting on the mutually abutting surfaces of the Part 126 and plate 114 have a layer of epoxy adhesive

109845/1191

brings up. In the yoke 102 - in contrast to the slot 40 in the winding tape core 16 according to FIG. 2 - no slot is required, since the eddy current paths in the magnet yoke 102 through an insulating layer on each of the blanks 128 and 130 are interrupted.

A middle loop 132 of part 126 serves together with a cap 136 (Pig. 5) of the tube 108 as a stop for the armature 118, and since the leg 132 is laminated, it allows the working gap 122 of the electromagnet 100 is placed in the middle of the coil window 104, without high eddy current losses occurring, as would otherwise be the case if instead of the leg 132 a not bleached stop would be used. The loop 132 should be as clear as possible in the coil window 104 extend. - Furthermore, in the construction according to FIGS. 5 and 6, a shorter tube 108 can be used for the anchor will. Since the tube 108 is massive and therefore a relatively large amount of heat is generated in it by the eddy currents, is achieved by a shorter tube 108 that the amount of heat generated by the electromagnet 100 is reduced. A shorter tube 108 also withstands the pressure medium pressure prevailing in it more easily, and consequently a shorter tube 108 also have a thinner wall thickness, which improves the overall behavior of the electromagnet results. An additional advantage of this construction is that a shorter anchor is used and that this can be untidy,

The tube 108 for the armature has a tubular member 134 which is welded or soldered to a magnetic steel cap 136 (see. Fig. 5) is connected. The wall of the tubular member 134 is just thick enough to withstand the working pressure in pipe 108. The cap 136 has a thickness about twice that

10 9 8 4 5/1191

of the element 134, since the cap 136 not only has to withstand the working pressure, but also the impact of the anchor 118. The tubular element 134 is made of semi-austenitic Formed material and has a non-magnetic portion 138 and a magnetic portion 140, namely for the same reasons as detailed above with reference to the tube 20 of the thrust electromagnet 12 after Pig. 1 were explained. The tube 108 may be connected to the side plate 114 in any suitable manner, such as by welding will.

A top 142 of the anchor 118 should as in Pig.

5 shown to be arranged in its normal position.

In this position, the top 142 is flush with the inner surface 144 of the plate 112.

The invention is also based on the knowledge that the width W (Pig x 5) of the coil 106 preferably in one certain ratio to the length L (Pig. 5) of the working gap 122 of the electromagnet 100 should be. The preferred one Ratio is in the range

3 H Ϊ i61,

i.e., in other words, the ratio W / L should be between 3 and 6 lie. A preferred dimensioning is W Λ * 6.35 mm and L ^ 1.59 mm.

Fig. 7 shows another embodiment of one according to the invention High pressure pull solenoid 150 similar in many respects to that described above with reference to FIG described electromagnet 100 is similar.

The pull electromagnet 150 according to Pig. 7 has a magnet yoke 152 defining a coil window 154, also a conventional toroidal coil 156 (to which connecting lines 158 are connected), which is located in the coil window 154 is arranged, and a hollow, cylindrical tube 160

10 9 8 4 5/1191

"- 19 -

for ilen anchor, which has a tubular element 161 and a Has cap 163 and centered in the magnet yoke 152 and the Coil 156 is arranged and extends through a circular opening 162 in a side wall 164 of the magnetic jooh 152 extends out of this. Just like with the electromagnet 100 of FIG. 5, the cap or lid 163 is approximately twice as thick as the tubular element 161 and is welded or soldered to this. A solid cylindrical anchor 166 is connected to a pull pin 168 and arranged axially displaceably on a cylindrical recess 170 of the tube 160. The electromagnet 150 is in its unexcited or "normal" position shown, When energized, the armature 166 moves through a working gap 172 upwards (based on FIG. 7) in order to actuate a pressure medium valve (not shown), e.g. the valve 10 of Fig. 1.

8 shows an enlarged illustration of the armature 166. This has a stack 174 of individual sheet metal blanks 176 on; this stack 174 has been turned or ground to a cylindrical shape, and a magnetic one Sleeve 178 has been pressed onto the stack 174 over the entire length thereof. This sleeve 178 holds the sheet metal blanks 176 in their cylindrical configuration. A thin longitudinal section 180 of the sleeve 178 is turned off in order to obtain an extremely thin wall thickness, e.g. from 0.18 to 0.23 mm.

The thin section 180 of the sleeve 178 is that section which is within the magnetic circuit of the Electromagnet I50 should be. The thin-walled section 180 results in a minimum of electrical losses in the core and holds the sheet metal blanks 176 in their cylindrical shape Configuration or arrangement without the need for any additional connection between them, e.g.

109845/1191

an epoxy glue to hold the sheet metal blanks together. A thicker portion 182 of the sleeve 178 that is outside the magnetic circuit is left thick, so that the desired overall stability results. The section 182 is long enough to accommodate two rivets 184 going through sleeve 178 and all Sheet metal blanks 176 extend. All rivets (e.g. 184) lie outside the magnetic circuit and therefore do not contribute to the electrical losses in the core. Of the Section 182 also advantageously extends beyond one end 186 of the stack 174 for a good connection with the pull pin 168, for example by connecting it to the bottom 188 of the sleeve 178. Preferably there is a small distance (of about 0.025 mm per side for an electromagnet for 400 Hz) between the anchor 166 and the inside of the tube 160 is provided. A longitudinal groove 190 (see FIG. 8) on the outside 192 of the armature 166 enables the necessary flow of pressure medium between a valve (not shown) and the working gap 172. The groove 190 can alternatively can also be designed as a slot which extends through the entire wall thickness of the sleeve section 180.

The electromagnet 150 according to Pig. 7 has a similar structure like the electromagnet 100 according to FIG. 5, with the exception that the magnet yoke 152 according to FIG. 7 is a single one Has stack of rectangular sheet metal blanks, which have a simple, rectangular window 152 for form coil 156. The magnet yoke 152 has none Middle leg 132 like the magnet yoke 102 according to FIG It can be manufactured more cheaply than the magnet yoke 102 according to Fig. 5, inter alia because it can be manufactured in one piece. Both for the electromagnet 100 according to Fig «. 5 as for the electromagnet 150 according to FIG

109845/1191

one of the three anchors 118, 166 and 194 according to fig. 5 or, 7 or 9 can be used.

Fig. 9 shows an alternative embodiment of an armature 194 for use in the electromagnet 150 (Fig. 7), In the armature 194, a sleeve 196 (which does not need to be magnetic, like the sleeve 178 according to FIG. 8) is only partially pressed over the longitudinal extension of a stack 198 of individual sheet metal blanks 200, which are cylindrical in shape have been turned off or ground down »The sheet metal blanks 200 can also be glued or the like. together but because of the sleeve 196 the required strength of such a connection, e.g. Glued connection, very small. The tube 160 of FIG. 7 surrounds the individual Bleohzusohnitte 200 and helps them to stick together in the right position.

In operation, that part of the armature 194 that is not in the sleeve 196 is always within the tube 160 7. If the sheet metal blanks 200 are sufficiently thick and therefore rigid, no glue or other Connection required. A preferred construction assumes thin sheet metal blanks in the middle area of the stack 198 200 to achieve good electrical properties and on the outside of the stack 198 thick sheet metal blanks 200 should be used to obtain the required strength. Two rivets 202, only one of which is shown extend through the sleeve 196 and all sheet metal blanks 200 to form a single, monolithic unit obtain. The force from the armature 194 is (for example, on a valve similar to the valve 10 of FIG. 1) via the Transfer sleeve 196 and not directly through the sheet metal blanks 200. A pull pin (not shown) can for example be connected to a power transmission rivet 204 that is transverse to the inner diameter of the

109845/1191

Sleeve 196 extends. The sleeve 196 and all rivets 202 are outside the magnetic circuit and thus do not contribute to the core losses of the electromagnet 150.

Low pressure pull electromagnet

The low-pressure pull-up electromagnet according to the invention is identical to the high-pressure pull-up electromagnets described above 100 and 150 of Fig. 5 and 7, with the exception that the tube for the low-pressure electromagnet the inclusion of the armature is designed as a very thin, completely magnetic tube of high strength, as is was described above for the low-pressure thrust solenoid. - -

The preferred embodiments of the invention described above related to the use of Electromagnet according to the invention for actuating hydraulic valves. However, it should be expressly pointed out that that the use is in no way limited to such hydraulic valves, but that one use is also possible with any other valve, e.g. with pneumatic valves, gas valves, valves for the electronically controlled fuel injection, also for any other type of control or regulation, even without the use of valves. - The valves according to the invention can be made entirely of a layer of epoxy resin or the like. be surrounded. The anchor and the recesses for the anchor preferably have in the present invention a circular cross-section, but other shapes are possible such as square, rectangular, and elliptical. It is also possible to use the construction shown in FIGS a thrust electromagnet can be built. To do this, a

109845/1191

blown stop and a non-magnetic push pin used

Further refinements and modifications of the invention within the scope of the general on which it is based Ideas of the invention are possible.

Patent attorneys Dipl.-Ing. Horst R öse Dipl.-Ing. Peter Kosel

109845/1191

Claims (8)

3353 Bad Ganderehelm, April 8, 1971 P.O. Box 129 Hohenhöfen 5 Telephone: (05382) 2842 Telegram address: Siedpatent Badgandersheim Our file no. 2 5 56/2 GW Lisk Co., Inc.
Patent application dated April 8, 1971 Patent claims SJ thrust electromagnet with one in a tube underneath Reinforcement of a magnetic force axially displaceably arranged armature for actuating a device, preferably one Valve, characterized in that a laminated magnet yoke (16) is provided with a coil window (17) provided therein, which yoke (16) in opposite Side walls (38, 39) each have an opening (36, 37) that a ring coil (18) is arranged in the coil window (17) and is provided with a central opening which is approximately coaxial with the two openings (36, 37) that the Tube (20) through these two openings (36, 37) and through, the central opening of the annular coil (18) extends and on its Underside is provided with a stop (28) which is provided with an axial recess (26) through which a push pin (24) resting against the armature (22) extends out of the electromagnet (12), and that the upper side of the tube (20) is provided with a seal (80, 92, 94) to prevent liquid from escaping. 2. Electromagnet according to claim 1, characterized in that the ratio of the coil length (X) to the length (Y) of the Working gap of the armature (22) is in the range from about 3 to 6 » 109845/1191 3. Electromagnet according to claim 1 or 2, characterized in that the tube (20) consists of a semi-austenitic Material is made which is treated so that it is at two sections (54 »56) in the area of the magnet yoke (16) magnetic and non-magnetic in a section (58) lying between these two sections (54, 56) is. 4. Electromagnet according to one of claims 1 to 3 »characterized in that the magnetic yoke (16) at least a slot (40) for the flow of eddy currents in concentric with the axis of the electromagnet (12) To prevent paths (42). 5. Electromagnet according to one of claims 1 to 4 _f, characterized in that the armature (22) has a thin, approximately parallel to the axis of the electromagnet (12) extending slot (60), the bottom (62) at an angle to the longitudinal axis of the Electromagnet (12) runs in order to obtain a solid area in the middle of the armature (22) for the contact of the push pin (24) «, 6. Electromagnet according to one of the preceding claims, characterized in that a manually operable Device (30) for the preferred control by hand is arranged at the upper end of the tube (20) and one having an actuating button (84) connected to a push rod (92) which is in contact with the armature (22) can be brought to move this by hand into its excited state, and that to prevent fluid leakage provided seal has an O-ring seal (94), the O-ring sealing against the with the actuating button (84) connected push rod (92) rests. 10 9 8 4 5/1191 7. Pull electromagnet with an armature which is arranged axially displaceably in a tube under the action of a magnetic force for actuating a device, preferably a valve, characterized in that a laminated magnet yoke (102; 152) with a coil window (104; 154) provided therein is provided, which only in its lower side wall (114; 164) has a recess (112; 162) that a ring coil (106; I56) is arranged in this coil window, the center of its central opening approximately with that of the recess (112; 162) of the magnet yoke agrees that the tube (110; 160) is arranged in the recess (112; 162) and the central opening, and that it is _{open at its lower end at the one side wall N} (114; 164) of the magnet yoke its upper end at the other side wall of the magnet yoke is closed (136; 163). 8. Electromagnet according to claim 7 »characterized in that the closed end of the tube (110; 160) is arranged directly on the inside of the other side wall of the magnetic yoke (102; 152). 9. Electromagnet according to claim 7 or 8, characterized in that the magnet yoke (152) substantially Is rectangular and has stamped sheet metal blanks, which in parallel to the longitudinal axis of the Electromagnet (150) extending plane, the magnet yoke two short and two longer side parts and its one recess (162) is circular and the tube (160) for the armature (166) is connected to the magnet yoke (152) at this recess (162) » 10o electromagnet according to one of claims 7 to 91 characterized in that the ratio of coil length 109845/1191 (W) to the length (L) of the working gap of the anchor in the area from about 3 to 6. 11 β electromagnet according to one of claims 7 to 10, characterized in that the tube (134) is made of semi-austenitic material which is so treated is that it is in a section (HO) in the area of the magnetic yoke (102, 114) magnetically and in an area (138) the coil (106) is non-magnetic. (Fig. 5). 12. Electromagnet according to one of claims 7 to 11, characterized in that the magnetic yoke (102) has a central, axial, laminated projection (132) which extends into the central opening of the coil (106) up to a certain depth 13. Electromagnet according to claim 12, characterized in that the armature (118) is solid and has a slot (120) running parallel to the longitudinal axis of the electromagnet, around the eddy currents in this Reduce armature, and that the magnet yoke (102) facing End of the armature in the non-excited position of the armature (see Fig. 5) with approximately the inside of the lower one The side wall (114) of the magnet yoke (102) is aligned. 14. Electromagnet according to one of claims 7 to 13 » characterized in that the armature (166; 194) is a cylindrical stack (174; 198) of individual sheet metal blanks (176; 200) which run parallel to the axis of the electromagnet, and that a sleeve (178; 196) is provided which with a tight fit over at least a portion of the longitudinal extension of the stack is applied to the sheet metal blanks (176; 200) to hold together « 15. Electromagnet according to claim 14, characterized in that an armature tension pin (168) is connected to the sleeve (178; 196) ₀ 109845/1191 16. Electromagnet according to claim. 14 or 15 »by this characterized in that the sleeve (178) has a first, very thin-walled section (180) which extends approximately over that part of the longitudinal extension of the armature (166) which extends within the magnet yoke (102; 152) is arranged. 17. Electromagnet according to claim 16, characterized in that that the sleeve (178) has a second, thicker portion (182), which approximately that part the length of the armature (166) which remained outside of the magnetic yoke (102; 152) 18. Electromagnet with an armature for operating a device, gate part of a valve, characterized in that that the anchor (166; 194) has a stack (174; 198) of individual sheet metal blanks (176; 200) which run parallel to the longitudinal axis of the armature, and that a sleeve (178; 196) is provided which is closely fitted over at least a portion of the longitudinal extent of the stack is applied. 19. Electromagnet according to claim 18, characterized in that that an anchor tension pin (168) is connected to the sleeve (178; 196). 2Oe electromagnet according to claim 18 or 19 »thereby characterized in that the sleeve (178) has a first, very thin-walled section (I80) which extends approximately extends over that part of the longitudinal extent of the armature (166) which is arranged within the electromagnet (150) is" 21. Electromagnet according to claim 20, characterized in that that the sleeve (178) has a second, thicker portion (182), which approximately that part the length of the stack (174) which remains outside of the electromagnet (150). 109845/1191 22. Electromagnet with an axially displaceable arranged in a tube under the action of a magnetic force Armature for actuating a device, preferably a valve, characterized in that the tube (20; 134) is made of semi-austenitic material, which is treated so that it is in a section (54, 56; 140) is magnetic and is non-magnetic in a second section (58; 138) (Fig. 1, 5) « 23. Electromagnet with a generated under the action of a ring coil through which an alternating current flows Magnetic field in the area of a working gap movable armature, characterized in that the ratio of Coil length (X; W) to the length of the working gap (Yj L) is approximately in the range from 3 to 6. 24. Electromagnet with an axially displaceable arranged in a tube under the action of a magnetic force Armature for actuating a device, preferably a pressure medium valve or in a system with low Pressure medium pressure, characterized in that a magnet 3och and a coil arranged in this are provided that the tube is arranged within the coil and magnet yoke is, and that it is completely magnetic and very thin-walled and has a high strength. 25. Electromagnet, preferably an alternating current operated electromagnet, with a push pin, characterized in that that the push pin (24) has approximately the following composition, which gives it a Rockwell hardness of approximately 60 and non-magnetic properties gives: Cobalt $ 45 to $ 50 Chromium $ 27 to $ 32 Tungsten 14 to 19 ° / o Carbon 2 to 4 % Tantalum or niobium $ 2 to $ 7 Manganese 1 to 3 ^c ß> Iron 2 to 5 ^a 'o. 10 9 8 A 5/119 1