SI20931A

SI20931A - Pin or treenail

Info

Publication number: SI20931A
Application number: SI200100147A
Authority: SI
Inventors: Miroslav Smrdel
Original assignee: Smrdel Miro S.P. Predelava Plastičnih
Priority date: 2001-05-29
Filing date: 2001-05-29
Publication date: 2002-12-31

Abstract

The patent deals with a pin (1; 10) or treenail for dry assembly by driving them in, or connecting by a leading lengthy section of rated diameter and an anchoring section. Along the core (2; 11) there are exclusively circular ribs. The external diameter of leading ribs (3; 12) determines the rated diameter of the treenail or pin, while the external diameter of anchoring ribs (4; 13) is equal for all ribs, but larger than the rated one. The thickness of the leading ribs (3; 12) is smaller than the thickness of the anchoring ribs (4; 13). The distance between the ribs (3, 4; 12; 13) is uniform and equal to the distance between the last of the anchoring ribs (4; 13) from the corresponding core end (2; 11). The core (2; 11) is cylinder-shaped or conical and full. The anchoring ribs (4; 13) are uniformly divided, so that they consist of semi-ribs (4a) or quarter-ribs (4b). The leading rib (12) is represented by an integral or divided circular body.

Description

SMRDEL MIRO s.p. P 2001 OSMRDEL MIRO s.p. P 2001 O

Predelava plastičnih mas, kovinska galanterija, elektro izdelki, orodjarstvoPlastics processing, metal fancy goods, electrical products, tool making

Brezovica pri Ljubljani, SlovenijaBrezovica near Ljubljana, Slovenia

Zatič oziroma moznikPin or dowel

Predmet izuma je zatič oziroma moznik za suho zabijalno pritrjevanje oziroma spajanje z uvodnim dolžinskim odsekom imenskega premera zatiča oziroma možnika in njemu sledečim sidrirnim odsekom.The subject of the invention is a pin or a dowel for dry driving fastening or joining with the introductory length section of the nominal diameter of the pin or the male and the anchor section thereafter.

Pod pritrjevanjem razumemo vgraditev z zadevnim zatičem opremljenega predmeta v vnaprej pripravljeno prirejeno dimenzijsko obstojno izvrtino in pod spajanjem povezovanje dveh objektov, od katerih vsak ima vnaprej pripravljeno prirejeno dimenzijsko obstojno izvrtino za sprejem zadevnega moznika.By attachment we mean the installation of an object in question with a corresponding pin into a pre-fabricated dimen- sion-proof bore, and by joining two objects, each having a pre-fabricated dimen- sion-resistant bore for receiving the said dowel.

Zatič za suho zabijalno pritrjevanje uvodoma definirane vrste je znan naprimer iz patenta EP 0 544 054 Al. Le-ta je dvodelen in obsega votel sidrirni tulec, katerega sidrirni dolžinski odsek je površinsko strukturiran in vzdolžno prerezan, in v njem gladek zabijalni razpirni zatič. Premer sprejemne izvrtine za zadevni zatič je v osnovi prirejen imenskemu premeru zatiča. Omenjena površinska struktura pri tem obsega izmenično ploščate kolute, katerih premer presega imenskega oziroma se na prednjem koncu zatiča z imenskim ujema, nakar postopno raste, in masivne vence imenskega premera in trapeznega preseka, ter v osni diametralni ravnini potekajoče togostne vezi, ki premoSčajo vrzeli med ploščatimi koluti in masivnimi venci. Pri vstavitvi zatiča, kar tudi poteka z zabijanjem, se omenjeni ploščati koluti ob stiku z ustjem izvrtine nagnejo vsak na svojo soležno konično ploskev masivnega venca in z zabitjem omenjenega razpirnega zatiča v tulec, ko je ta vložen, se slednji obodno razpre, kar je omogočeno z omenjenim vzdolžnim razporkom,The dry bolt fixing pin of a predefined type is known, for example, from EP 0 544 054 Al. It is two-part and comprises a hollow anchor sleeve whose anchor length section is surface-structured and longitudinally cut, and a smooth drive-in expansion pin. The diameter of the receiving hole for the pin in question is basically adapted to the nominal diameter of the pin. Said surface structure here comprises alternately flat discs whose diameter exceeds the nominal or at the front end pins with the nominal fit, and then gradually grows, and the massive rims of the nominal diameter and trapezoidal cross section, as well as in the axial diametrical plane of a rigid bond bridging the gaps between flat wheels and massive wreaths. When inserting the pin, which is also driven by a pin, said flat discs, when in contact with the mouth of the bore, tilt each to their sole conical surface of the solid rim and, by inserting said expansion pin into the sleeve, when inserted, the latter circumferentially opens, which is possible with said longitudinal spacing,

-2ο pri čemer se v mejah, ki jih določa stena izvrtine, površinska struktura sidrirnega dolžinskega odseka v sebi še dodatno elastoplastično preoblikuje.-2ο wherein, within the limits defined by the borehole wall, the surface structure of the anchorage length section within itself is further elastoplastically reshaped.

Pomanjkljivost rešitve iz zgornje reference je v dvodelnosti naprave, zaradi česar je imenski premer zatiča na dol praktično omejen, kot tudi v tem, da je kakovost vgraditve dejavnik, ki je odvisen od več naključnosti.The disadvantage of the solution mentioned above is in the two-part of the device, which makes the nominal diameter of the pin downwards practically limited, as well as the fact that the quality of the installation is a factor that depends on more coincidence.

Moznik za suho zabijalno spajanje uvodoma definirane vrste je znan naprimer iz patenta US 3,883,258. Gre za spajanje drugega z drugim izrecno lesenih delov. Moznik je v osnovi rahlo konično telo z vso dolžino možnika zaobsegajočim vzdolžnim razporkom, katerega globina sega domala do osi moznika, pri čemer je površina moznika tako strukturirana, da obstaja niz obročastih zob, ki v osnem preseku spominjajo na zobe žage, s tem da zunanji premer obročastih zob od prednjega konca moznika proti zabijalnemu koncu raste. Sidranje moznika v prirejeni izvrtini lesenega predmeta temelji na predpostavki, da se elastoplastično preoblikujejo na eni strani zobje moznika, k čemur pripomore omenjeni vzdolžni razporek, in na drugi stena izvrtine.The dowel for dry plugging of a predefined type is known, for example, from US patent 3,883,258. It is about joining one another to another with explicit wooden parts. The dowel is basically a slightly conical body with the entire length of the span encompassing a longitudinal spacer, the depth of which extends almost to the axis of the dowel, the surface of the dowel being so structured that there are a series of annular teeth that resemble the saw teeth in the axial section, with the outer the diameter of the annular teeth grows from the anterior end of the dowel towards the entraining end. The anchorage of the dowel in the adapted bore of the wooden object is based on the assumption that the elastoplastic reshapes on one side of the dowel teeth, to which the said longitudinal gap contributes, and on the other, the borehole wall.

Pomanjkljivost rešitve iz zgornje reference je v tem, da je le-ta praktično omejena na les, kot tudi spet v tem, da je kakovost vgraditve dejavnik, ki je odvisen od več naključnosti.The disadvantage of the solution mentioned above is that it is practically limited to wood, and again that the quality of installation is a factor that depends on more coincidence.

Cilj izuma je ustvariti zatič oziroma moznik, ki bo invarianten glede imenskega premera oziroma dolžine in bo kakovost vgraditve v bistvu invariantna glede naključnosti.It is an object of the invention to provide a pin or dowel that is invariant in nominal diameter or length and that the quality of installation is essentially invariant with respect to randomness.

Pri zatiču oziroma mozniku po izumu za suho zabijalno pritrjevanje oziroma spajanje z uvodnim dolžinskim odsekom imenskega premera zatiča oziroma moznika in njemu sledečim sidrirnim odsekom so vzdolž sredice zatiča oziroma moznika razporejena izključno le z njo integralna in z njo soosna prečna kolutasta rebra. S tem se dobi izdelek, ki je v izdelovalnem pogledu izjemno ugoden.In the case of a pin or dowel according to the invention, for the dry bolt fixing or joining with the introductory length section of the nominal diameter of the pin or dowel and the subsequent anchor section, only integral and coaxial transverse annular ribs are arranged along the center of the pin or dowel. This produces a product that is exceptionally advantageous in a manufacturing perspective.

Zunanji premer na uvodnem dolžinskem odseku zatiča oziroma moznika nahajajočega se oziroma nahajajočih se uvodnih reber po izumu določa imenski premer moznika oziroma zatiča in je zunanji premer na sidrirnem odseku zatiča oziroma moznika nahajajočih se sidrirnih reber, ki je za vsa zadevna rebra smotrno enak, večji od imenskega. Tako odpadejo zadrege, ki so v stanju tehnike pogoste, glede določanja prave velikosti svedra za določen zatič oziroma moznik.The outer diameter at the introductory length section of the pin or dowel of the located or located introductory ribs according to the invention determines the nominal diameter of the dowel or pin and the outer diameter at the anchor section of the pin or dowel of the anchor ribs, which is substantially the same for all concerned ribs, is greater than noun. Thus, embarrassments, which are common in the prior art, regarding the determination of the right drill size for a particular pin or dowel are eliminated.

Debelina na uvodnem dolžinskem odseku zatiča oziroma moznika nahajajočega se oziroma nahajajočih se uvodnih reber, ki je v primeru dveh ali več reber za vsa zadevna rebra smotrno enaka, je po izumu prednostno manjša od debeline na sidrirnem odseku zatiča oziroma moznika nahajajočih se sidrirnih reber, ki je za vsa zadevna rebra smotrno spet enaka. Ker uvodna rebra niso nosilna, se s tem ukrepom pridobi na dolžini za sidrirna rebra in vsaj nekaj malega se tudi prihrani pri gradivu.The thickness at the introductory length section of the pin or dowel of the located or located leading ribs, which in the case of two or more ribs is substantially the same for all the ribs concerned, is preferably less than the thickness of the anchor section of the pin or dowel of the anchor ribs, which is reasonably the same again for all the ribs concerned. Since the opening ribs are not load-bearing, this measure is obtained at length for the anchor ribs and at least a small amount is also saved in the material.

Razmik med rebri, uvodnimi in sidrirnimi, je prednostno enoten in enak odmiku zadnjega od sidrirnih reber od tamkajšnjega konca sredice moznika oziroma zatiča. S tem je zagotovljeno homogeno deformacijsko stanje reber po vgraditvi.The distance between the ribs, introductory and anchor, is preferably uniform and equal to the distance of the last of the anchor ribs from the local end of the center of the dowel or the pin. This ensures a homogeneous deformation state of the ribs after installation.

Sredica zatiča oziroma moznika je prednostno valjasta oziroma konična in polna. S tem je zagotovljena potrebna togost elementa pri zabijanju.The core of the pin or dowel is preferably cylindrical or conical and full. This ensures the necessary rigidity of the hammer element.

Sidrirna rebra so po izumu uniformno deljena v eni oziroma dveh osnih diametralnih ravninah, tako da tedaj sestojijo iz pol- oziroma četrtreber z vmesnima režama med njima oziroma vmesnimi režami med njimi. Z delitvijo reber na pol- oziroma četrtrebra se izognemo nevarnosti, da bi se kolutasta rebra, če bi bila krožnikasta, v vgrajenem stanju obodno zgubala.According to the invention, the anchor ribs are uniformly divided in one or two axial diametrical planes, so that they then consist of half or quadruples with intermediate slots between them or intermediate slots between them. By dividing the ribs into halves or quarters, there is no danger of the ring ribs, if they are circular, collapsing circumferentially.

Uvodna rebra so po izumu prednostno celovite kolobarjaste tvorbe, ni pa izključena možnost, da so, analogno s sidrirnimi rebri, tudi ta uniformno deljena v eni oziroma dveh osnih diametralnih ravninah, tako da tedaj sestojijo iz pol- oziroma četrtreber z vmesnima režama med njima oziroma vmesnimi režami med njimi. S tem omogočimo vgraditev zatiča oziroma sornika tudi v izvrtino, katere premer je manjši od im-44 enskega.According to the invention, the introductory ribs are preferably complete annular formations, but it is not excluded that, in analogy with the anchor ribs, these ribs are uniformly divided in one or two axial diametrical planes, so that they then consist of half- or four-ribs with intermediate regimes between them, respectively. intermediate slots between them. This enables the pin or bolt to be mounted in a bore whose diameter is smaller than that of an im-44.

Izum v nadaljnjem pobliže predstavljam na osnovi nekaj vzorčnih primerov izvedbe zatiča, ne da bi se nanje kakor koli omejeval, tu v povezavi z vzorčnim pridržalom kot napravo za suho vgraditev, v danem primeru zabitje, v prirejeno izvrtino v ležečem ali pokončnem gradbenem nosilcu za pridržanje oziroma držanje oziroma vpetje oziroma pritrditev linijskega vodnika, prednostno, a ne izključno, kabla oziroma cevi, ne da bi se tudi v zadevi uporabe predmetnega zatiča kakor koli omejeval na tu predstavljene vzorčne primere. Strokovnjaku z zadevnega področja ne bo problem ugotoviti, da se da predstavljene zatiče same kot take brez nadaljnjega uporabiti kot moznike, pa se zato podrobnemu opisovanju moznikov iz praktičnih razlogov smem odreči.Hereinafter I present the invention in more detail on the basis of some exemplary embodiments of the pin, without being limited in any way, here in conjunction with the sample retainer as a device for dry mounting, optionally ramming, into a modified bore in a recessed or upright holding bracket or holding or attaching or attaching a line conductor, preferably, but not exclusively, to the cable or pipe, without limiting itself to the exemplary examples presented here, even in the case of using the subject pin. It will not be difficult for one of ordinary skill in the art to recognize that the presented pins themselves can be used as dowels themselves without further ado, and therefore, for practical reasons, I may refuse to describe the dowels in detail.

Na priloženem listu skic kažeIt shows in the attached sketch sheet

SL. 1 predmetni zatič v povezavi z enojnim pridržalom v narisni projekciji,FIG. 1 subject pin in conjunction with a single retainer in outline projection,

SL. 2 predmetni zatič v povezavi z dvojnim pridržalom v narisni projekciji,FIG. 2 subject pin in conjunction with a double retainer in outline projection,

SL. 3 prerez zatiča po črti III-III s SL. 1,FIG. 3 is a cross-sectional view of a pin along line III-III of FIG. 1,

SL. 3a prerez po črti III-III s SL. 1 v primeru modficirane izvedbe,FIG. 3a is a cross-sectional view taken along line III-III of FIG. 1 in the case of a modified embodiment,

SL. 4 prerez zatiča po črti IV-IV s SL. 2,,FIG. 4 is a cross-sectional view of a pin along line IV-IV of FIG. 2 ,,

SL. 4aFIG. 4a

SL. 4b prerez po črti IV-IV s SL. 2 v primeru modficirane izvedbe, in prerez po črti IV-IV s SL. 2 v primeru še nadaljnje modficirane izvedbe.FIG. 4b is a sectional view taken along line IV-IV of FIG. 2 in the case of a modified embodiment, and a cross-section along line IV-IV of FIG. 2 in the case of a further modified embodiment.

Zatič I po SL. 1 ima konično polno sredico 2, dva niza z njo integralnih in z njo soosnih vzdolž katere se nahajata prečnih kolutastih reberThe pin I of FIG. 1 has a conical full center 2, two rows with integral and coaxial along which transverse annular ribs are located

-5i.s. pri tankem koncu sredice 2, smotrno na odmiku od le-tega, niz uvodnih reber 3, katerih zunanji premer je imenski premer zatiča, in na preostalem delu sredice 2 niz sidrirnih reber 4, katerih zunanji premer je večji od imenskega.-5i.s. at the thin end of the core 2, preferably at a distance from it, a series of introductory ribs 3 whose outer diameter is the nominal diameter of the pin, and at the rest of the core 2 a series of anchor ribs 4 whose outer diameter is larger than the nominal diameter.

Izum predvideva, da je debelina uvodnih reber 3 manjša od debeline sidrirnih reber 4, s tem da je v odvisnosti od potrebne elastične podajnosti izbranega gradiva, smotrno poliamida, za funkcioniranje zatiča merodajna debelina sidrirnih reber 4.The invention provides that the thickness of the introductory ribs 3 is less than the thickness of the anchor ribs 4, depending on the required elastic yield of the selected material, suitable polyamide, for the functioning of the pin is the appropriate thickness of the anchor ribs 4.

Število uvodnih reber 3 je navzgor omejeno smotrno na dve rebri, medtem ko je število sidrirnih reber 4 načeloma poljubno, vendar v odvisnosti od izbrane dolžine zatiča tako izbrano, da so razmiki med rebri 3, 4 medsebojno enaki in enaki odmiku zadnjega sidrirnega rebra 4 od debelega konca sredice 2, kjer je k zatiču 1 priključen aktualni gradbeni del, tu enojno pridržalo P.The number of opening ribs 3 is limited upwards to two ribs, while the number of anchor ribs 4 is in principle arbitrary, but depending on the selected pin length, such that the spacing between ribs 3, 4 is equal to one another and equal to the distance of the last anchor rib 4 from the thick end of the core 2, where the current construction part is connected to pin 1, here is a single restraint P.

Medtem ko sta v osnovni izvedbeni različici zatiča 1 uvodni rebri 3 celovita koluta, so sidrirna rebra 4 v diametralni osni ravnini, ki je v tem predloženem primeru izvedbe vzporedna s sprejemno osjo pridržala P, deljena, tako da vsako sidrirno rebro 4 sestoji iz dveh polreber 4a z režama 5 med njima (SL. 3).While in the basic version of the pin 1, the introductory ribs 3 are integral reels, the anchor ribs 4 in the diametrical axial plane, which in this embodiment is supported by the retaining axis P, are divided such that each anchor rib 4 consists of two half ribs. 4a from slot 5 between them (FIG. 3).

Medtem ko delitev sidrirnih reber 4 v eni diametralni ravnini zadošča za zatiče 1 manjših imenskih premerov, pa so sidrirna rebra 4 zlasti v primeru zatičev 1 večjih imenskih premerov, ko je debelina in s tem togost sidrirnih reber 4 samoumevno večja, deljena smotrno v dveh diametralnih osnih ravninah i.s. v že omenjeni prvi diametralni osni ravnini kot tudi še v drugi, ki je pravokotna na prvo. Tako vsako sidrirno rebro 4 sestoji iz štirih četrtreber 4b s štirimi režami 6 med njimi (SL. 3a).While dividing the anchor ribs 4 in one diametrical plane is sufficient for pins 1 of smaller nominal diameters, anchor ribs 4 are particularly, in the case of pins 1 of larger nominal diameters, when the thickness and thus stiffness of anchor ribs 4 is obviously greater, divided expediently into two diametrical ones. axial planes is in the aforementioned first diametrical axial plane as well as in the second perpendicular to the first. Thus, each anchor rib 4 consists of four quarters 4b with four slots 6 between them (Fig. 3a).

Premer sprejemne izvrtine se ravna po imenskem premeru zatiča 1, t.j. zunanjem premeru uvodnih reber 3. Pri zabijanju zatiča 1 v prirejeno sprejemno izvrtino sidrirna rebra 4 drugo za drugim zadenejo ob ustje izvrtine in se pri napredoval nem zabijanju krožnikasto elastično upognejo nazaj in tako deformirana vstopijo v izvrtino; v njej s svojo akumulirano energijo elastične deformacije pritiskajo ob steno izvrtine in po načinu trneka varujejo zabiti zatic 1 proti izvlečenju.The diameter of the receiving bore is aligned with the nominal diameter of pin 1, i.e. outer diameters of the introductory ribs 3. When the pin 1 is inserted into the adapted receiving hole, the anchor ribs 4 are hit one after the other by the mouth of the hole and, in the case of advanced ramming, bend the circular elastic back and thus become deformed into the hole; in it, with their accumulated energy, the elastic deformations are pressed against the wall of the bore and, by the method of the hook, they secure the driven pins 1 against the pull out.

Razume se, da imajo iz pol- 4a oziroma četrtreber 4b sestavljena sidrirna rebra 4 'mehkejšo' deformacijsko karakteristiko.It is understood that pole 4a and quaternary 4b, respectively, have anchored ribs 4 with a 'softer' deformation characteristic.

Bistvena lastnost zatiCa 1 v zasnovi po SL. 1 je, da so pri zabijanju sidrirna rebra 4 od rebra do rebra 'trša', kar je dobrodošlo denimo v primerih vgradnje, ko oblikovna obstojnost sprejemne izvrtine ni na vsej dolžini enotna.An essential feature of pin 1 in the design of FIG. 1 is that when hammering, the anchor ribs 4 from rib to rib are 'harder', which is welcome, for example, in cases of installation where the design stability of the receiving bore is not uniform throughout.

Za vgraditvene primere, ko je zagotovljena na vsej dolžini enotna oblikovna obstojnost sprejemne izvrtine, pa je tedaj primernejša izvedbena različica zatiCa 10 po skici SL. 2, kjer je k zatiCu 10 priključen aktualni gradbeni del, tu dvojno pridržalo PP. .However, for mounting cases where uniform design stability of the receiving bore is ensured throughout, then the embodiment 10 of FIG. 10 is more suitable. 2, where the current construction part is connected to pin 10, here the double arm of the PP is held. .

Zatic 10 ima valjasto polno sredico 11 in eno samo uvodno kolutasto preCno rebro 12. Kar zadeva zasnovo sidrirnih reber 13 in število ter porazdelitev reber 12, 13 vzdolž sredice 11, je primer izvedbe po SL. 2 tudi lahko enak predhodnemu. Bistvena vgraditvena razlika med primeroma je, da pri slednjeomenjenem primeru izvedbe vsa sidrirna rebra 13 enako 'držijo'.The pin 10 has a cylindrical full core 11 and a single introductory annular cross rib 12. With regard to the design of the anchor ribs 13 and the number and distribution of ribs 12, 13 along the core 11, an embodiment of FIG. 2 can also be the same as the previous one. The essential fitting difference between the examples is that in the latter embodiment, all anchor ribs 13 are "held" equally.

Skici SL. 4a in SL. 4b pa slednjič ponazarjata možnost tudi izvedbene različice, pri kateri je tudi uvodno rebro 12 deljeno na dve pol- 12a oziroma štiri Cetrtrebra 12b z režama 14 med njima oziroma režami 15 med njimi. Izum s tem predvideva tudi vgraditveno možnost, ko bi premer sprejemne izvrtine utegnil biti pod imensko mero zatiea.Sketches FIG. 4a and FIG. 4b, for the last time, illustrate the possibility of an embodiment, in which the introductory rib 12 is also divided into two poles 12a and four four-ribs 12b from the slots 14 between them or slots 15 between them. The invention also provides for the possibility of mounting when the diameter of the receiving bore could be below the nominal dimension of the pin.

Če pridržalo P, PP odmislimo in namesto njega k zatiCu 1, 10 soosno zrcalno priključimo njemu enak zatic 1, 10, dobimo prikladen moznik.If we consider the retainer P, PP, and attach the same pin 1, 10 to it with pin 1, 10, we obtain a suitable dowel.

Claims

Patent claims

A pin (1; 10) or a dowel for dry driving or fastening with an introductory length section of the nominal diameter of the pin or dowel and the anchor section thereafter, characterized in that along the center (2; 11) of the pin (1; 10) or dowels exclusively arranged with integral integral and coaxial transverse annular ribs.

Pins or dowels according to claim 1, characterized in that the outer diameter at the introductory length section of the pin or dowel of the located or located leading ribs (3; 12) determines the nominal diameter of the dowel or pin and is the outer diameter at the anchor section of the pin or the dowel of the located ribs (4; 13), which is substantially the same for all concerned ribs (4; 13), larger than the nominal ribs.

3. The pin or pin according to claim 1 or 2, characterized in that the thickness is at the introductory length section of the pin or pin of the extending or extending ribs (3; 12), which in the case of two or more ribs (3; 12 ) for all concerned ribs (3; 12) is substantially the same, preferably less than the thickness at the anchor section of the pin or dowel of the located ribs (4; 13), which is preferably again the same for all concerned ribs (4; 13).

A pin or dowel according to any one of the preceding claims, characterized in that the distance between the ribs (3, 4; 12, 13) is uniform and equal to the distance of the last of the anchor ribs (4; 13) from the local end of the core (2; 11) ).

A pin or dowel according to any preceding claim, characterized in that the core (2; 11) is cylindrical or conical and preferably full.

A pin or dowel according to any one of the preceding claims, characterized in that the anchor ribs (4; 13) are uniformly divided in one or two axial diametrical planes, such that they then consist of a semi- (4a) or quaternary (4b) with intermediate slots (5) between them or intermediate slots (6) between them.

A pin or a possible according to any one of the preceding claims, characterized in that the introductory rib (12) or the introductory ribs (3) or the introductory ribs are preferably integral circular structures or / are / are, analogous to the anchor ribs ( 4; 13), uniformly divided in one or two axial diametrical planes, so that they then consist of semi (12a) and quaternary (12b) with intermediate slots (14) between them or intermediate slots (15) between them.