DE2401576C3 - Retraction device for hose-connected dental handpieces - Google Patents

Description

The invention relates to a retraction device for hose-bound dental handpieces, consisting of consisting of two round hose guide disks and a deflecting body arranged between the latter having pulley for the hose, which is in a carriage movable on a guide track is stored, which is supported at both ends on the guide track, the carriage on the Guide track under the effect of a pull-out force exerted by pulling on the handpiece hose in the pull-out direction and under the action of a retraction force triggered by pulling on the handpiece hose in the retraction direction is movable.

Retraction devices of this type are shown in the DE-OS 22 21130 and DE-AS 15 66210. In these known devices is the carriage on its underside by means of rollers on the guide track supported, while a further roller arranged on its upper side resiliently against the ceiling an insert arranged in a swivel arm is applied to resiliently in the case of DE-AS 15 66 210 Snap-in openings in the ceiling to be able to snap into place. The one on the pulley or on the one with the Retraction force acting on the slider connected to the deflection roller by means of a pull-back force on the swivel arm or on the insert arranged tension spring in the form of a helical spring or a spiral spring is generated, the free end of which is attached via a pull rope or directly to the slide.

The pivot arm and thus the track can be adjusted in the case of DE-AS 15 66 210 in inclination so that the guideway can assume an inclined position. Such an inclination of the However, the guideway has no influence on the retraction of the hose, since this retraction is carried out by itself the clock spring is effected.

In the retraction device known from DE-OS 22 21 130, a locking of the extended Hose can only be done in the extended end position with the aid of the locking device.

In the known from DE-AS 15 66 210

Retraction device can lock the extended hose only in very specific few, Pull-out positions dependent on the arrangement of the snap-in openings take place. It also provides two known devices, the coil spring with pulling rope exerting the retraction force or the Clock springs and their storage on the swivel arm and the attachment to the slide el ^ en relatively high effort.

Another retraction device of the type mentioned is known from DE-OS 22 04 744. There the guideway is essentially one vertical guide rod on which the slide is supported by means of sliding elements. at When the pull-out force ends, the slide is fixed on the guide rod in that it clamped firmly to the guide rod by a spring-loaded ring-shaped clamping element will. A loosening of this clamping element in order to take effect by the dead weight of the Deflection roller including slide caused retraction force can only be achieved by exercising a relatively strong jerky tightening of the hose in the pull-out direction. Apart from the fact that the clamping element causes notches and the like in the guide rod when firmly clamped, this can occur at The strong, jerky pulling out of the hose, which is difficult for the dentist to control, can damage it of the handpiece and the hose. The notches mentioned can be the sliding elements damage and thus impair the exact guidance of the slide on the guide rod. By the Frequent jamming of the clamping element, it can happen that the clamping element is deformed, whereby a secure clamping effect is called into question.

The invention is based on the object of providing a retraction device of the type mentioned at the beginning create, which avoiding retraction springs and allowing only a gentle -to Tightening the hose to loosen the slide fixed on the guideway is not a force-fit Jamming of the slide with the guideway is conditional.

To solve this problem, it is proposed according to the invention that the guideway as in Extension direction rising inclined plane is formed, wherein the retraction force exerted on the carriage is formed by the slope force of the slide, and that the one pointing in the retraction direction Support of the slide located at the end of the slide with the handpiece tube pulled out in the respective position braking friction element is formed, the frictional engagement due to a train exerted on the slide on the handpiece hose, in the sense of lifting the one pointing in the direction of withdrawal The tilting moment acting on the slide is outweighed by the downhill force of the slide, while the support located on the end of the slide pointing in the pull-out direction auo a roll t> o or sliding element.

The retraction device formed in the above-mentioned manner has no spring for the Exercise of the withdrawal force. The retraction force exerted on the slide is rather determined by the> '"' Downhill force (gravitational force) of the guideway formed in the form of an inclined plane located Schli'terts formed.

Another difference to the known retraction devices is the subject of the application at the end pointing in the retraction direction, the slide is supported by a Friction element formed. The frictional engagement (frictional force) of the friction element as a result a tilting moment that is exerted on the slide when the handpiece tube is pulled and acts in the sense of lifting the slide end pointing in the retraction direction outweighed by the downhill force of the slide, so that the dentist just took the hose under slow release must hold in order to maintain the said overturning moment and the hose through the downhill force mentioned by the pulley and the hose section located on the latter loaded slide is withdrawn.

As soon as the dentist completely releases or lets go of the hose, the aforementioned tilting moment no longer acts the slide in such a way that the slide end which is directed in the retraction direction and has the friction element descends on the guideway and the frictional engagement of the friction element pushes the slide brakes and locks immediately, without impairments such as notches in the guideway be evoked. This also prevents damage to the friction element.

The proposed retraction device thus has compared to the known devices The advantage is that the carriage can be locked in any position, with the omission a retraction spring is a very simple, inexpensive construction of the designed as a compact unit Retraction device is achieved, especially since a special storage and attachment of such No spring.

The friction element works together with the guide track, which is designed as an inclined plane, without jamming, which results in freedom from wear, so that the retraction device always works trouble-free.

While the one mentioned known retraction device because of its substantially vertical Guide track can only be installed in such device bodies that have the necessary length of the Guide track have appropriate height, z. B. in equipment cabinets standing on the 3oden or Equipment stands, the proposed retraction device can also be flat, essentially horizontal Extending device bodies, such as instrument tables or the like., Can be installed.

If, according to one embodiment, the deflecting roller is in an elongated one that receives the deflecting roller axis Recess of the carriage is mounted longitudinally movable, the additional advantage is achieved that when Pull out the deflection roller until the stop of the Umlenkroilenachse on the one pointing in the pull-out direction Moved end of the elongated recess, whereby the friction element relieved weight and the Frictional engagement is noticeably reduced and thus only a relatively low pull-out force on the Handpiece or the hose needs to be exercised.

When the pull-out force ends, the pulley moves due to its own weight up to Stop of the deflection roller axle on the end of the elongated recess pointing in the retraction direction back, so that the friction element is weighted and the immediate stop of the carriage

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causes.

The elongated recess, which is expediently designed in a straight line, can be parallel to the guide track or extend inclined up to the vertical, it being most advantageous if the elongated recess runs parallel to the guideway, because then only a very small additional force is necessary to the deflection roller at the beginning of the pull-out up to the stop of the deflection roller axle in the pull-out direction facing end of the elongated recess to move.

In order to achieve that the frictional engagement of the friction element with the guide track when retracting of the hose is completely canceled, it is proposed that the carriage consist of two by Cross sections connected to one another, the pulley exists between receiving side walls, in which the recesses designed as slots for the storage of the pulley axis are provided and that the circumference of the hose guide disks protrudes over the Unteräme of the carriage side walls and the hose guide disks can be supported on the guide track of the friction element while Jas rolling or sliding element on a parallel to and higher than the guideway of the friction element lying guide track part is supported, and that at the end pointing in the extension direction of one of the slots an automatic resilient latching and releasing pawl is arranged for the UmienkroHenachse.

If, in this embodiment, a pull-out force is exerted on the deflection roller, it moves again the deflection roller until the stop of the deflection roller axis on the end of the as pointing in the pull-out direction Slit formed! Anglichen recess, whereby the friction element is relieved of weight and the frictional engagement is significantly reduced and thus only a relatively small pull-out force to be exerted on the handpiece or the hose needs. When the mentioned stop is reached or when the pull-out force ends, the locks Deflection roller axis in the automatic resilient input and Disengage. so that now the pulley as a result this lock cannot move back.

Because the friction element and the rolling or sliding element are supported at different heights, the slots are more inclined than the guide track and the guide track part. The consequence of this is that the deflection roller axis runs "uphill" in the latter during extension, i.e. during its movement towards the end of the v> slot pointing in the extension direction, so that the hose guide disks previously rolling on the guide track lift off the guide track. As a result of this lifting off, the slide now rests solely on the friction element and the rolling or sliding element, so that the friction element that is now loaded comes into effective frictional engagement with the guideway. The slide cannot now run back.

If the hose is to be withdrawn , the dentist only needs to gently and carefully retighten the hose once, whereby the automatic resilient latching and disengaging pawl adjusts itself for the unlatching, so that when the hose slackens the deflection roller axis moves out of position. and disengaging pawl disengages and runs back so far in the slot in the direction of its retracting end until the hose guide disks come into contact with the guideway and the pulley axis comes into contact with the upper edge of the slot. The distance between the upper edge of the slot and its lower edge, ie the slot width, is slightly larger than the diameter of the Unlenkroüerr axis. As a result of the contact of the deflection roller axis with the upper edge of the slot, the deflection roller axis now lifts the end of the slide, which has the friction element, off the guide path, on the one hand as a result of the aforementioned contact with the upper edge of the slot and, on the other hand, as a result of the support of the hose guide disks on the guide track, so that the frictional engagement of the friction element with the guide track is completely eliminated in that the friction element lifts off from the guide track. The pulley axis can now, under the influence of the retraction force formed by its downhill force and the downhill force of the carriage, execute a retraction movement without the dentist - as in the aforementioned embodiments - needing to exert a tightening force on the hose.

The withdrawal movement ends when the dentist makes a short and gentle pulling movement on the Hose exerts, so that the pulley axis back into the automatic resilient latching and releasing pawl engages and thus the aforementioned frictional engagement is restored, or if that in the retraction direction Pointing end of the slide on a closing wall or the like of the guide way strikes.

It is also possible to pull out again immediately or to pull out further from the locking position mentioned, because the pulling force then exerted relieves the friction element. Upon termination This pull-out force first disengages the deflection roller axle from the engagement and disengagement pawl, so that for the desired locking of the pulley axis after such a re-extension repeated brief and light retightening must be carried out.

Both during the pull-out movement of the hose also with its withdrawal movement as well as with the working position for the dentist corresponding, At a standstill, the rolling or sliding element is constantly supported on the guideway.

It is useful. when the pulley each preferably circular rolling disks of smaller size on the outside of the hose guide disks Has diameter than the hose guide disks, wherein the Abrollschcibcn and the hose guide disks are arranged coaxially and that expediently on the inner sides of the carriage side walls Rolling rails for the rolling disks running parallel to the slots are arranged.

This ensures that the deflection roller axis is relieved during its movement in the slot, especially in the direction of the end of the slot pointing in the retraction direction , as it no longer has to transmit the unwinding forces to the slot edges alone because the unwinding disks now roll on the unwinding rails in a supporting manner until the pulley shaft comes into contact with the top edge of the slot. The deflection roller axis is no longer decisive for the number of revolutions of the deflection roller. Before or when the friction element is lifted off the guide track while a retraction movement is being carried out, the rolling disks lift off the rolling rails.

When the diameter of the rolling disks is the same

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the diameter of the deflecting body, the advantage is achieved that at the beginning of the movement Deflection roller axis in the slot in the direction of the end of the slot pointing in the retraction direction, the rolling up of the hose on the deflection body corresponds to the roll-off of the roll-off disks on the roll-off rails and thus also with the retraction movement of the Umienkrolle. This ensures that that the retraction movement after the pulley axis has disengaged from the latching and releasing pawl starts immediately.

Provided that the deflection body, the hose guide disks and the rolling disks are against each other arranged rotatably on the pulley axis, it is achieved that only the with the guide track is in Engaging hose guide disks or only those engaging with the rolling rails Rolling disks perform a rotational movement while the other disks perform this rotational movement do not run with.

An expedient embodiment is obtained when depending on the outer sides of the slide side walls a rolling or sliding element is arranged and if the guide track for the friction element through the Web part of a rail with a U-shaped cross-section and the guide track part for the two rolling or Sliding elements are formed by the edges of the flange parts of the U-shaped rail.

Due to the flange parts of the U-shaped rail, a particularly effective lateral guidance of the in the Rail used carriage reached.

If the flange parts are made sufficiently thick, several U-shaped ones can be arranged next to one another Rails each use one and the same flange part for the rolling or sliding elements of adjacent carriages Find.

In the drawing, embodiments of the invention are shown by way of example. It shows

F i g. 1 the retraction device in the corresponding standstill of the working position for the dentist Slide seen from the side.

F i g. 2 the retraction device during the retraction movement, this state also being the rest position for the dentist, when viewed from the side,

F i g. 3 the retraction device during the pull-out movement in a view from the side,

4 shows a section along the line IV-IV in FIG and

F i g. 5 shows a section along the line V-V in FIG. 3.

The retraction device has a pulley 1, which consists of two hose guide disks 2,3 and the actual deflection body 4 consists. A hose 5 is located between the two hose guide disks 2, 3 around the deflecting body 4. On the one shown in FIGS. 1 to 3 is the end of the hose 5, not shown a dental handpiece connected. The provided at the end of the hose 5 shown Connector 6 is used for connection to a line leading to a supply device. Through the Through the hose 5, the dental handpiece can be supplied with compressed air, water, electricity or the like.

The pulley 1 is mounted in a slide 7, which is movable on a guide track 8 designed as an inclined plane rising in the extension direction A. The slide 7 is supported at its two ends 9, 10 on the guide track 8 The pulley 1 is under the action of a pull-out force movable on the guide path 8 in the extension direction and under the action of a return force in the retraction direction R.

The support of the slide on the guide track 8 located at the end 9 pointing in the retraction direction R is formed by a friction element 11, while the support located on the slide end 10 pointing in the extension direction A consists of a rolling or sliding element 12.

The deflecting roller 1 is mounted in an elongated recess 14 of the carriage 7, which receives its axis 13 and is designed as a slot, so that it can move longitudinally with respect to the carriage. The elongated recess 14 runs inclined to the guide track 8, ie it rises more sharply in the extension direction A than the guide track 8.

The carriage 7 consists of two cross struts, for. B. 15, 16, interconnected, the pulley 1 between receiving side walls 17, 18. In these side walls 17, 18 are the elongated Recesses 14 are provided for mounting the deflection roller axle 13.

The hose guide disks 2, 3 of the pulley 1 stand over the lower edge of the carriage side walls 17, 18 before. The hose guide disks 2, 3 can be supported on the guide track 8.

The friction element 11 consists of a friction lining applied to the cross strut 15. on the other hand The entire cross strut 15 can also consist of a friction material. The rolling or sliding element 12 is on a parallel to and higher than the guide track 8 of the friction element 11 Guide track part 8a superimposed.

At the end of one of the slots 14 pointing in the extension direction A , an automatic, resilient latching and releasing pawl 19 for the deflecting roller axle 13 is arranged. For the engagement of the pulley shaft 13, the latching opening 20 of the latching and disengaging pawl 19 is the pulley shaft has a latching pin 21 at its end. B. work on the type of mechanical switch shown in DT-OS 19 14 914. The latching and releasing pawl 19 is designed in the form of a flat hook which, at its end pointing in the extension direction A, is mounted on the slide side wall 17 or 18 such that it can pivot about an axis 22. Under the action of a spring 23, the latching and releasing pawl 19 tries to rotate clockwise about the axis 22. However, it rests against two locking pins 24.

If a pull-out force is now exerted on the hose 5 in pull-out direction A , the pulley 1 rotates clockwise. The deflection roller axle 13 moves from the slide shown in FIG. 2 into the position shown in FIG. 3 position, the locking pin 21 slides over the beveled hook end of the locking and unlocking pawl 19 and the in F i g. 3 assumes the position shown at the end of the pull-out force, the locking pin 21 takes the position shown in FIG. 1 position. If a gentle, brief retightening force is now exerted on the hose 5 again, the deflection roller axle 13 moves out of the position shown in FIG. 1 in the position shown in FIG. 2 position, the locking pin 21 slides under a run-on surface 25 projecting obliquely out of the plane of the pawl 19 and the pawl 19 bends elastically out of its plane at least at its end pointing in the retraction direction

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Latching pin 21 the part of the pawl 19 pointing in the retraction direction, in order then to move further into the position shown in FIG. 2 apparent location to move.

The deflection roller 1 has a circular one on each of the two outer sides of the hose guide disks 2, 3 Rolling disks 26, 27, which have a smaller diameter than the hose guide disks 2, 3. the Rolling disks 26, 27 and the hose guide disks 2, 3 are arranged coaxially. On the inside of the Carriage side walls 17, 18 are parallel to the as Rolling rails 28, 29 running in slots formed by elongated recesses 14 for the rolling disks 26, 27 of the deflection roller 1 located between the carriage side walls 17, 18. The roll-off rails 28, 29 are shown in FIGS. 1 to 3 can be seen because the slide side walls are made of transparent or translucent material.

The rolling or sliding element 12 consists according to FIG. 4 from two individual elements 12a and 126. A rolling or sliding element 12a, t2b is arranged on each of the outer sides of the slide side walls 17, 18. The guide track 8 for the friction element 11 is formed by the web part (FIG. 5) of a rail with a U-shaped cross section and the guide track part 8a for the two rolling or sliding elements 12a, i2b by the edges of the flange parts of the U-shaped rail. According to FIG. 1 to 3

consist at least the flange parts of the U-shaped rail made of transparent or translucent material. At the end pointing in the extension direction A , the guide track 8 is provided with an end plate 30 which serves as a stop for the carriage 7 and which is provided with a passage opening for the passage of the hose coming from the connector 6. A plate corresponding to the end plate 30 can also be provided at the other end of the guide track (not shown).

In the F i g. 4 and 5, the hose 5 is omitted for the sake of clarity.

In particular, the upper cross strut 15 of the slide 7 advantageously serves as a tube guide member, especially when the dentist returns the tube 5 to the retraction device faster than the slide 7 moves in the retraction direction R.

The handpiece, not shown, connected to the hose 5 is z. B. according to the type of DT-OS 19 14 914 can be held in a suitable holder in the rest position. As can be seen in particular from Figure 4, the diameter of the rolling disks 26, 27 is equal to the diameter of the deflecting body 4. The deflecting body 4, the hose guide disks 2, 3 and the rolling disks 26, 27 are each against one another rotatably arranged on the deflection roller axis 13.

In addition 5 sheets of drawings

Claims (8)

Patent claims: 1. Retraction device for hose-bound dental handpieces, consisting of a two round hose guide disks and a deflection roller for the hose which is arranged between the latter and which is mounted in a carriage movable on a guide track, which is supported at both ends on the guide track, the The slide on "> the guideway can be moved in the pull-out direction under the action of a pull-out force exerted by pulling on the handpiece hose and in the pull-back direction under the action of a pull-back force caused by pulling the handpiece hose, is characterized in that the guideway (8) as in pull-out direction (A) rising inclined plane is formed, the retraction force exerted on the slide is formed by the downhill force of the slide (7), and that the support of the end (9) located at the end (9) pointing in the retraction direction (R) Slide (7) by a slide (7) When the handpiece hose (5) is pulled out, a friction element (11) that decelerates in the respective position is formed, the frictional engagement of which is formed as a result of the slide end (9 ) pointing in the retraction direction (R) being exerted on the carriage (7) when the handpiece hose (5) is pulled ) acting tilting moment is outweighed by the downhill force of the slide, while the support on the slide end (10) pointing in the withdrawal direction (A) consists of a rolling or sliding element (12). 2. Retraction device according to claim 1, characterized in that the deflection roller (1) in a die Deflection roller axis (13) receiving elongated recess (14) of the carriage (7) longitudinally movable is stored. 3. Retraction device according to claim 2, characterized in that the elongated recess (14) runs parallel to the guideway (8) or inclined up to the vertical. 4. Retraction device according to claim 3, characterized in that the carriage (7) consists of two by cross struts (15, 16) interconnected, the deflection roller (1) between receiving side walls (17, 18), in which the formed as slots Recesses (14) are provided for the mounting of the deflection roller axis (13) and that the circumference of the hose guide disks (2,3) protrudes over the lower edge of the slide side walls (17, 18) and the hose guide disks (2, 3) on the guide track (8) of the friction element (U) can be supported, while the rolling or sliding element (12) is supported on a guide track part (Sa) lying parallel to and higher than the guide track (8) of the friction element, and that at the end of one pointing in the pull-out direction (A) the slots (14) an *> ° automatic resilient latching and releasing pawl (19) for the pulley axis (13) is arranged. 5. Retraction device according to claim 4, characterized in that the deflection roller (1) is circular Rolling disks (26, 27) of smaller diameter "" '' ser than the hose guide disks (2, 3), the rolling disks (26, 27) and the hose guide disks (2, 3) are arranged coaxially and that on the carriage (7) parallel to the slots extending roll-off rails (28, 29) for the roll-off disks (26, 27) are arranged. 6. Retraction device according to claim 5, characterized in that the diameter of the rolling disks (26, 27) is equal to the diameter of the deflecting body (4) 7. Retraction device according to claim 5 and / or 6, characterized in that the deflecting body (4), the hose guide disks (2, 3) and the rolling disks (26, 27) against each other are rotatably arranged on the pulley axis (13). 8. Retraction device according to one of claims 4 to 7, characterized in that a rolling or sliding element (12a, 12b) is arranged on the outer sides of the slide side walls (17,18) and that the guide track (8) for the friction element (ti ) are formed by the web part of a rail with a U-shaped cross-section and the guide track part (Sa) for the two rolling or sliding elements (12a, 12b) by the edges of the flange parts of the U-shaped rail.