EP0272339B1 - Mécanisme d'avance pour un outil de honage abrasif - Google Patents

Mécanisme d'avance pour un outil de honage abrasif Download PDF

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Publication number
EP0272339B1
EP0272339B1 EP19860117850 EP86117850A EP0272339B1 EP 0272339 B1 EP0272339 B1 EP 0272339B1 EP 19860117850 EP19860117850 EP 19860117850 EP 86117850 A EP86117850 A EP 86117850A EP 0272339 B1 EP0272339 B1 EP 0272339B1
Authority
EP
European Patent Office
Prior art keywords
friction
honing tool
tool according
adjusting
shank
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19860117850
Other languages
German (de)
English (en)
Other versions
EP0272339B2 (fr
EP0272339A1 (fr
Inventor
Peter Baum
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Maschinenfabrik Gehring GmbH and Co KG
Original Assignee
Maschinenfabrik Gehring GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=8195664&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0272339(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Maschinenfabrik Gehring GmbH and Co KG filed Critical Maschinenfabrik Gehring GmbH and Co KG
Priority to EP19860117850 priority Critical patent/EP0272339B2/fr
Priority to ES86117850T priority patent/ES2019581B3/es
Priority to DE8686117850T priority patent/DE3676310D1/de
Publication of EP0272339A1 publication Critical patent/EP0272339A1/fr
Application granted granted Critical
Publication of EP0272339B1 publication Critical patent/EP0272339B1/fr
Publication of EP0272339B2 publication Critical patent/EP0272339B2/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B33/00—Honing machines or devices; Accessories therefor
    • B24B33/02—Honing machines or devices; Accessories therefor designed for working internal surfaces of revolution, e.g. of cylindrical or conical shapes

Definitions

  • the invention relates to a honing tool according to the preamble of claim 1, as is known for example from DE-A1 2 908 422.
  • Reaming tools usually have a long service life. Therefore, they do not have to be readjusted very often to compensate for wear. It is therefore customary to use the mechanical setting devices with which the reaming tools are manually preset to the bore size to be produced, also for adjusting when the tool is worn.
  • Such delivery devices can be arranged as setting devices on the tool itself or on an adapter for receiving the tool and enable the friction surfaces to be widened by hand using an adjusting nut.
  • the invention has for its object to design the generic honing tool so that the delivery device can transmit high feed forces with avoidance of elastic deformations and preloads with a structurally simple structure.
  • the arrangement of the adjusting nut forming the actuator on a threaded section of the tool shank enables the actuating forces to be applied directly to the shank by means of an automatically actuated adjusting device which in turn acts directly on the adjusting nut. No linkage is required for the transmission of the delivery forces, which would lead to deformations and thus to inaccuracies in the setting.
  • the adjusting nut moves the friction sleeve on the shaft.
  • the delivery device is of a very simple design and can be used not only for automatic adjustment but also for the automatic presetting of the reaming tool.
  • 1 has a preferably cylindrical shaft 2, which has a clamping end 3 for attachment to a honing machine (not shown), an adjoining threaded section 4, and a conically widening shaft part 5.
  • the shaft part 5 carries a known friction sleeve 6, which is provided on its outer circumference with a cutting surface 7, e.g. an electroplated diamond layer.
  • An actuator designed as an adjusting nut 8 is screwed onto the threaded section 4 of the shaft 2 and has a toothing 9 on its outer circumference.
  • the friction sleeve 6 is fixed in the axial direction on the shaft part 5 between a pressure ring 10 and an end disk 13 arranged at a distance from the front end 12 of the shaft 2.
  • the pressure ring 10 is supported on an end face 11 of the adjusting nut 8.
  • the face plate 13 is aligned with a centering lug 14 concentrically with the friction sleeve 6 and non-positively connected to the shaft 2 via a pull rod 15. It interacts with a spring assembly 16 surrounding it, which is arranged in a blind bore 17 running coaxially in the shaft part 5.
  • the Federpa ket is clamped between an end collar 18 of the pull rod 15 and a closure disk 19. It closes the bore 17 and is firmly connected to the shaft 2, preferably screwed.
  • the pull rod 15, which is guided through the closure disk 19 and the end disk 13, has a threaded end section 20, onto which a nut 21 is screwed, which in the assembled position rests against the end face 22 of the end disk 13.
  • the end plate 13 is pressed under the force of the spring assembly 16 against the annular end face 24 of the friction sleeve 6.
  • the ratios are chosen so that the axially directed machining forces occurring during the honing process cannot cause an undesired displacement of the friction sleeve on the shaft 2.
  • the adjusting nut 8, the shaft 2 or the shaft part 5 and the pull rod 15 with the spring assembly 16 form an expansion device 1a for the friction sleeve 6.
  • the adjusting device 25 consists essentially of a toothed rack 26 which can be brought into engagement with the toothing 9 of the adjusting nut 8 by means of a first adjusting cylinder 27 (FIG. 2) via a sliding piece 30 guided in guides 28, 29. In this position, the toothed rack 26 is displaceably guided in a groove-shaped recess 33 with a second adjusting cylinder 31 transversely to the tool axis in a cross piece 32 which is firmly connected to the sliding piece 30.
  • the adjusting cylinder 27 and the guides 28, 29 are mounted in a fixed position on a bracket 34 fixedly attached to the machine stand (not shown).
  • the piston rod 35 of the adjusting cylinder 27 is connected to the sliding piece 30 via two drivers 36 (FIG. 2). They are firmly screwed to the sliding piece 30 and engage with a nose-shaped projection 37 in an annular groove 38 of the piston rod 35.
  • the conditions are such that there is play on all sides between the piston rod 35 and driver 36 transversely to the axial direction of the piston rod, as a result of which any misalignment between the adjusting cylinder 27 and the sliding piece 30 is harmless.
  • the drivers 36 protrude in opposite directions over the sliding piece 30.
  • Adjustable stop screws 39 are screwed into the projecting sections, which stop on an adjacent end face 40 of the guides 28 and 29 when the toothed rack 26 is in engagement with the adjusting nut 8.
  • the adjusting cylinder 31 is mounted transversely to the adjusting cylinder 27 on the crosspiece 32 in alignment with the rack 26 so that its center axis lies approximately in the center plane of the rack 26.
  • the piston rod 41 of the adjusting cylinder 31 is connected directly to the rack 26 by means of two drivers 42.
  • the drivers 42 engage with nose-shaped projections 43 in an annular groove 44 on the piston rod 41.
  • the stroke of the adjusting cylinder 31 is preferably chosen so large that it corresponds to a full tooth pitch of the toothing 9. The stroke can also correspond to several full tooth pitches.
  • a fork 45 is secured, which secures the reaming tool against twisting during delivery.
  • two diametrically opposed wrench surfaces 46 are attached to the reaming tool between the cylindrical clamping end 3 and the threaded section 4, the wrench size of which corresponds to the opening 47 of the fork 45.
  • a counter-holding device 48 is provided in order to absorb the radially acting force component occurring during the infeed, which would otherwise force the tool away.
  • the counter-holding device 48 essentially consists of a two-armed lever 49 which is pivotably mounted on a support arm 50.
  • the lever 49 has an end 51 opposite the fork 45, which is preferably prismatic.
  • the support arm 50 is (in a manner not shown) rigidly connected to the console 34 or the machine stand (not shown).
  • the linkage 52 is adjustable in length in a known manner, e.g. by means of a turnbuckle screw 55, which enables a precise setting of the contact of the lever end 51 on the clamping end 3.
  • a second counter-holding device 56 which is arranged at a greater axial distance from the counter-holding device 48 and the tool 1.
  • a counter piece 58 is fastened to the lower free end of the tool 1 on a device plate 57 fixed on the machine side.
  • the readjustment cycle is triggered by a signal from a manual or preferably automatic metering device known per se and therefore not shown.
  • the reaming tool 1 moves in the axial direction into a predetermined position. In this position, the tool is located completely outside the workpiece, and the toothing 9 of the adjusting nut 8 is approximately at the height of the toothed rack 26.
  • a positioning drive which is known per se and therefore also not shown, then rotates the reaming tool into a predetermined angular position, which is selected in this way that the key surfaces 46 on the shaft 2 are aligned with the opening 47 of the fork 45.
  • the adjusting cylinder 27 is then subjected to low pressure, whereupon the piston rod 35 extends and the adjusting device 25 moves radially in the direction of the reaming tool 1.
  • the fork opening 47 receives the shaft 2 on its key surfaces 46 and the toothed rack 26 comes into meshing engagement with the toothing 9 of the adjusting nut 8.
  • the movement of the adjusting device 25 is limited in the exemplary embodiment shown (FIG. 2) by the stop screws 39, which are set so that the toothed rack 26 meshes with the adjusting nut 8 with little play.
  • This position is detected by a control device (not shown) which then increases the pressure in the adjusting cylinder 27.
  • the second adjusting cylinder 31 is subjected to high pressure. He then shifts the rack 26 by, for example, one tooth pitch.
  • the adjusting nut 8 which is in engagement with the toothed rack 26 is correspondingly rotated by a small angle. It causes an expansion of the friction sleeve 6 by a certain amount, e.g. 0.001 mm in diameter.
  • the honing tool 1 is secured against rotation by the fork 45 and held in position with respect to the predetermined machining axis by the counter-holding devices 48, 56.
  • the adjusting cylinder 27 and then the adjusting cylinder 31 first return to their starting position, the readjustment cycle is completed and the reaming tool is released for the next work operation.
  • the stroke of the adjusting cylinder 31 preferably corresponds to one or more full tooth pitches, which ensures in a simple manner that the toothing of the toothed rack 26 and adjusting nut 8 gap on tooth with each further readjustment. If tooth is on tooth in the worst case during the first adjustment, the rack 26 is first automatically moved by means of the adjusting cylinder 31 until the desired engagement position is reached. Only then is the pressure in the adjusting cylinder 27 increased and the actual readjustment carried out in the manner described. The initially low pressure in the adjusting cylinder 27 rules out damage between the toothed rack 26 and the adjusting nut 8.

Landscapes

  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Claims (15)

1. Outil de rodage (1) avec une tige (2), munie d'une section conique (5) qui supporte une douille frottante (6), et avec un dispositif d'avance, qui permet d'ajuster les surfaces frottantes sur un diamètre donné, et dont fait partie un dispositif d'élargissement (1a), qui comporte la section de tige conique (5) et présente un organe de réglage (8), qu'un dispositif de déplacement (25), situé à l'extérieur de l'outil de rodage (1), permet d'actionner automatiquement, la section de tige conique (5) et la douille frottante (6) étant alors mobiles l'une par rapport à l'autre, dans le sens axial, caractérisé en ce que la tige (2) présente une section filetée (4), et en ce que l'organe de réglage est un écrou (8) disposé sur la section filetée (4), et qui déplace la douille frottante (6), dans le sens axial, sur la section de tige conique (5), lors d'une rotation dans le sens du pas de vis.
2. Outil de rodage suivant la revendication 1, caractérisé en ce que l'écrou de réglage (8) présente une denture extérieure (9), qui peut engrener avec une crémaillère (26) du dispositif de déplacement (25).
3. Outil de rodage suivant l'une des revendications 1 et 2, caractérisé en ce que la douille frottante (6) est maintenue entre l'écrou de réglage (8) et un disque frontal (13), relié par force d'adhérence à la tige (2), par l'intermédiaire d'une barre de traction (15).
4. Outil de rodage suivant la revendication 3, caractérisé en ce que la barre de traction (15) est maintenue sur la tige (2) au moyen d'un ressort (16), réalisé de préférence sous forme de bloc-ressort, et qui s'appuie sur un collet extrême (18) de la barre de traction (15), situé à l'intérieur de la douille frottante (6), et sur un disque de fermeture (19), qui ferme l'extrémité opposée (6a) de la douille frottante (6).
5. Outil de rodage suivant la revendication 4, caractérisé en ce que la force du ressort (16) est supérieure aux forces d'usinage axiales, qui s'exercent sur la douille frottante (6).
6. Outil de rodage suivant l'une des revendications 4 et 5, caractérisé en ce que la douille frottante (6) peut se déplacer sur la section de tige conique (5), contre la force du ressort (16).
7. Outil de rodage suivant l'une quelconque des revendications 2 à 6, caractérisé en ce que la crémaillère (26) du dispositif de déplacement (25) peut engrener avec la denture extérieure (9) de l'écrou de réglage (8), au moyen d'un cylindre de déplacement (27), par l'intermédiaire d'une pièce coulissante (30) de préférence, guidée dans des glissières (28, 29).
8. Outil de rodage suivant l'une quelconque des revendications 2 à 7, caractérisé en ce que la crémaillère (26) peut se déplacer à la transversale de l'axe de l'outil, a l'aide d'un cylindre de déplacement (31).
9. Outil de rodage suivant la revendication 8, caractérisé en ce que la course du cylindre de déplacement (31) correspond au moins à une division complète de la denture (9).
10. Outil de rodage suivant l'une quelconque des revendications 1 à 9, caractérisé en ce que l'outil (1) est protégé contre tout risque de rotation à l'aide d'une fourche (45), pendant l'avance.
11. Outil de rodage suivant l'une quelconque des revendications 1 à 10, caractérisé en ce qu'un dispositif de contre-appui (48; 56) au moins est prévu pour absorber la composante de force radiale, qui s'exerce lors de l'avance.
12. Outil de rodage suivant la revendication 11, caractérisé en ce que le dispositif de contre-appui se compose d'un levier à deux bras (49), qui pivote sur un bras-support (50), et dont une extrémité (51) s'applique sur l'extrémité de serrage cylindrique (3) de la tige (2).
13. Outil de rodage suivant les revendications 8 et 12, caractérisé en ce que le levier (49) s'articule, par l'intermédiaire d'une tringle (52), avec un carter du cylindre de déplacement (31), prévu pour l'avance transversale de la crémaillère (26).
14. Outil de rodage suivant l'une quelconque des revendications 1 à 13, caractérisé par deux dispositifs de contre-appui (48; 56), qui s'appliquent sur l'outil de rodage (1), à une certaine distance axiale mutuelle.
15. Outil de rodage suivant l'une quelconque des revendications 1 à 14, caractérisé en ce que le dispositif de déplacement (25) est commandé manuellement et/ou automatiquement, par un dispositif de vérification connu en soi.
EP19860117850 1986-12-20 1986-12-20 Mécanisme d'avance pour un outil de honage abrasif Expired - Lifetime EP0272339B2 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP19860117850 EP0272339B2 (fr) 1986-12-20 1986-12-20 Mécanisme d'avance pour un outil de honage abrasif
ES86117850T ES2019581B3 (es) 1986-12-20 1986-12-20 Dispositivo de ajuste para una herramienta de bruñido por frotacion.
DE8686117850T DE3676310D1 (de) 1986-12-20 1986-12-20 Zustelleinrichtung fuer ein reibhonwerkzeug.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19860117850 EP0272339B2 (fr) 1986-12-20 1986-12-20 Mécanisme d'avance pour un outil de honage abrasif

Publications (3)

Publication Number Publication Date
EP0272339A1 EP0272339A1 (fr) 1988-06-29
EP0272339B1 true EP0272339B1 (fr) 1990-12-19
EP0272339B2 EP0272339B2 (fr) 1994-06-22

Family

ID=8195664

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19860117850 Expired - Lifetime EP0272339B2 (fr) 1986-12-20 1986-12-20 Mécanisme d'avance pour un outil de honage abrasif

Country Status (3)

Country Link
EP (1) EP0272339B2 (fr)
DE (1) DE3676310D1 (fr)
ES (1) ES2019581B3 (fr)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2194821A (en) * 1938-08-19 1940-03-26 Norton Co Honing machine
DE2619741C2 (de) * 1976-05-05 1985-12-05 Maschinenfabrik Gehring Gmbh & Co Kg, 7302 Ostfildern Zustellvorrichtung für ein Zerspanwerkzeug zum Bearbeiten von Werkstückbohrungen, insbesondere ein Honwerkzeug
FR2419142A1 (fr) * 1978-03-06 1979-10-05 Citroen Sa Tete de rodage
DE3421193A1 (de) * 1984-06-07 1985-12-12 Maschinenfabrik Gehring Gmbh & Co Kg, 7302 Ostfildern Verfahren zum zustellen eines honwerkzeuges und vorrichtung zum ausfuehren des verfahrens

Also Published As

Publication number Publication date
EP0272339B2 (fr) 1994-06-22
DE3676310D1 (de) 1991-01-31
ES2019581B3 (es) 1991-07-01
EP0272339A1 (fr) 1988-06-29

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