DE10123267A1 - Quick clamping device for fixed clamping bolt inside cylinder, has locking mechanism with spaced apart retainerless roller bodies supported by spring device - Google Patents

Abstract

The locking mechanism (3) for the piston (4) includes retainerless roller bodies (5) which are kept spaced apart along the ball path around the piston and cylinder (1). The roller bodies are supported on the underside by a spring device to prevent them from dropping down in a radial inwards direction. A piston can be moved by a pressurised medium in one direction to cooperate with the cylinder, and can be moved by an energy accumulator in the other direction. The piston cooperates with a locking mechanism comprising roller bodies which engage with a path in the outer periphery of the clamping bolt (2) in the locking position. An Independent claim is also included for a quick-clamping device in which the roller bodies forming the clamping bolt locking mechanism are kept evenly spaced apart around the outer periphery of the bolt by spacer parts.

Description

The invention relates to a quick release device with resilient Ball restraint according to the preamble of claim 1. Such Quick release device is for example with the subject of DE 296 15 613 U1 become known. This quick release device is one Interlocking shown with balls held in a circumferential ball cage are, with the lower end of the ball cage on one resilient O-ring supports.

The support on the O-ring takes place in such a way that the ball cage on it lower end face has an outward slope that is on the O- Ring acts in such a way that in the locked state of the device in a radially outward widening groove is displaced in the cylinder housing.

This type of resilient ball retention has proven itself, albeit with it high manufacturing costs are associated. The one receiving the bullets Ball cage must be manufactured with high precision.

For example, the radial ball track in the ball cage must be accurate of 2/100 mm can be processed. Furthermore, to secure the balls against  the upper peripheral edge of the ball cage is flanged radially be what is associated with high processing costs. The same applies in the rest for the attachment of the lower front bevel.

The use of an O-ring at the bottom of the piston, which is radial in a groove is displaceable, but has serious disadvantages. For one, there is Danger of water flowing through the central location hole for the retractable nipple penetrates into the device and is deposited on the piston crown. The springy O- Ring is therefore in the water and therefore tends to swell, causing it to loses its spring properties. In this case, however, the ball cage cannot be moved more axially and the lock remains - even with the corresponding one Moving the piston - maintained. This positive locking can can only be canceled by destroying the device itself.

Such a resilient O-ring has the disadvantage that together with Moisture can also penetrate chips to the piston crown, which Ring cuts and is destroyed in the long run, which also makes it his loses resilient properties and the entire device in one positively locked state that only by destroying the device can be canceled.

The maintenance of the known device is relatively high because with continuous use, the upper sealing sleeve used for sealing, which forms an axial stop for the ball cage, removed and cleaned must become. In addition, the ball cage and the O-ring must be removed and be cleaned. The entire inner bore must then be cleaned thoroughly and blown dry to then reinstall all parts. On this occasion, the various O-rings on the Sealing sleeve replaced because they were removed and the Reinstallation could be damaged.

Another disadvantage of the known device is that the central There are built-in internals, namely the sealing sleeve,  the ball cage and the o-ring. However, this is the case for various applications disadvantageous, which is that the central inner bore is perfect should be kept free of internals and only by surrounding inner walls of the piston should be formed. This is especially true when it comes to that that a reciprocating piston goes through this central inner bore is slidably arranged, which is able to pull the nipple from its locked position in a position lifted from the clamping device lift out.

The subject of DE 43 07 342 A1 is a further quick release Established with springy ball retention, in which the balls are radially displaceably mounted in a rigid ball cage with the Cylinder housing is connected. The actual spring action is through a several resiliently mounted and under the influence of a pressure medium in the Cylinder housing causes displaceable pistons.

This arrangement also has the disadvantage that because of the use of a rigid ball cage, the radially aligned raceways in the ball cage are subject to heavy pollution and therefore the balls in their Can hinder movement play. In this case, too Forced locking of the device only by partial destruction of the Device can be lifted.

Even if chips or dirty water penetrates through the central inner bore and located above the piston between the piston and the ball cage deposits, the function of the entire facility is questioned.

Another major disadvantage is that because of the rigid ball cage in the Comparison to the resilient ball cage according to DE 296 15 613 U1 the radial Raceways in the ball cage must now be machined to 1/100 mm, This ensures that everyone is evenly distributed around the circumference Balls also load transfer evenly to the assigned upper and lower surfaces in the ball cage. There are only minor differences  between adjacent ball seats, then some balls do not carry more with the load transfer while other balls are all the stronger load-bearing loads, so there is an overall risk that balls are damaged or there is high wear.

In this case, the lower, multi-spring piston can be inclined and tilt, which also brings the entire device into one positively locked state device.

With US 5184810 is another quick release device at the beginning known type, which works with cageless balls, which are evenly distributed over the circumference of one under the influence of a Pressure means displaceable pistons are arranged.

In this known device, however, there is the disadvantage that the balls as Securing against falling out each have center holes through which a spring wire reaches through. The balls are in the form of a ring Chain threaded on the spring wire and are therefore against radially inward Directed falling out of their careers secured when the retractable nipple is completely removed from the device.

The disadvantage here, however, is that the threading of the balls is extraordinary elaborate processing of the balls requires, because the balls on the one hand with appropriate central bores are provided and on the other hand also the balls have to be ground roughly barrel-shaped in order to be a cheap one To perform load transmission in the locked state.

After a hole in the ball core for the passage of the spring wire was created, the ball is thereby in its high load transmitting Area weakened, which is associated with the risk that the balls at high Stress burst or be deformed.  

Because of the high locking forces, the balls mentioned must be made from one brittle, high-hardened tool steel can be made, because of its brittle hardness no stretching allowed. In the event of accidental collisions of the Machining tools on the workpieces to be machined will be the entire Quick release device with its locking device so strong on impact claims that the brittle, hardened balls then burst.

The invention is therefore based on the object of a task cageless ball holder of a locking device according to the object US 5184 810 to further develop these so that the balls without the need mechanical processing are designed to carry high loads and against radial falling out are secured.

To achieve the object, the invention is characterized in that that the balls on revolving ball tracks of the piston and the cylinder are kept spaced and on the bottom by resting on a spring washer are secured against falling radially inwards.

With the given technical teaching there is the advantage that Rest of the balls on a substantially in the axial direction and possibly also in the radial direction spring-loaded spring washer the balls in their Ball tracks are secured against falling out. So that no longer exists Danger that when removing the retractable nipple from the central Bore the balls directed radially inward into the central one Drop the mounting hole.

This advantage is particularly evident when the quick release Device according to the invention not only works in a horizontal position, but in in an inclined position or even in a vertical position in which the balls are arranged one above the other and the entire spherical ring in one vertical plane is aligned.  

Such an arrangement is of course also workable if the Quick release device works in an overhead position.

So there is generally a resilient ball retention in a quick release Device claimed, which ensures that the balls are directed radially inwards falling into the central location hole is secured.

It is expressly pointed out that the invention relates to all Locking devices according to the prior art relates. So it comes does not insist on using a locking device as follows is described using several exemplary embodiments. It just comes to describe generally a resilient ball restraint that is ensures that the balls are prevented from falling radially inwards into the central location hole are secured.

There are several embodiments for this technical feature, all of them individually or in combination with each other claimed as essential to the invention become.

In a first embodiment of the invention it is therefore provided that the Spring washer made of individual separate and spaced apart Spring clips exist, with each ball on an associated spring clip rests and the spring clip is distributed close to the circumference of a spring ring are arranged.

A spring bearing is assigned to each ball, so to speak, with the spring clip in a preferred embodiment as a U-shaped spring loop is trained. It can be provided that the middle leg, on which the ball essentially rests on, the shape of the ball is adjusted.

Instead of such a U-shaped spring clip can of course also simple pen springs can be used. In this case, the middle leg  omitted. In addition to such pen springs, other spring elements can also be used are used, especially spring slats (these are spring Sheet metal elements), which are made of spring steel or plastic can.

Instead of such spring elements, which are preferably made of spring steel or Plastic springs are made, can also be brush-like spring elements be used. If the balls on a lower, revolving Brush are held, the bristles of the balls also obliquely upwards spring tension, the same desired effect is achieved, the balls against radially inward falling out of the raceways on the piston to back up.

Instead of the spring ring described here made of a plastic or Metal material (preferably spring steel) can also be cuff-shaped Spring sleeves are used, which are preferably made of a rubber or Plastic material are worked. This cuff-shaped body also ensures with its radially inward, possibly circumferential design resilient edge for a corresponding preload of the balls, so that these are held in their raceways on the cylinder and on the piston.

It is generally pointed out that the term "bullet" is general too understand is. Therefore, the more general description is given in the following description The term "rolling element" is used because when using such rolling elements not only balls can be used, but also barrel-shaped, elliptical or oval rolling elements.

It is important in the invention that the rolling elements themselves no longer have to be machined, in particular it can be a central perforation the rolling elements are dispensed with. Therefore, the balls - on the same Outer diameter related - transfer much higher loads.  

But this also has the advantage that the balls are essential less expensive material can be made and no longer from one hardened tool steel must exist.

It is therefore sufficient to provide the balls with a surface hardening that is designed, for example, as case hardening or nitriding. Because of the Accordingly, there are also relatively large sized balls Contact surfaces on the spring washer and also the corresponding ones opposite load-transferring bevels on the retractable nipple and Accordingly, pistons and cylinders can be manufactured cost-effectively because in these areas too there are no hardened and therefore difficult to process materials must be used.

The larger balls used here according to the invention have the rest The advantage that they are more elastic and therefore also good shock and shock forces can record without being destroyed. As a result, it can also Machining errors on the careers can be compensated very well, because due to the good elasticity of the balls, a corresponding compensation of machining errors in such a way that the balls then still act evenly load transfer due to slight deformations.

In another embodiment, it can be provided that in the Corresponding grooves are milled on the outer surface of the balls. The grooves are only in the foot area of the respective ball and the groove is from reached through a spring washer. The balls are threaded on the spring washer are, which is preferably designed as a flat spring. Such a flat spring is also called Seeger ring, which ensures that the balls are both radial outward springiness as well as a substantially axial have aligned resilience.

Because of the groove worked into the circumference of the balls, the high-load-transmitting core itself is not damaged and the balls can  therefore be designed to be highly elastic and yet load transfer evenly act without tending to burst when subjected to impact forces.

Together with the spring ring according to the invention, which is a resilient Ball restraint also forms the spacing agent between the rolling elements claimed as essential to the invention. This applies in Unique position also in connection with the spring ring previously claimed.

The spacing means that the rolling elements at a distance from each other keep distributed around the circumference, can be designed in various ways.

First, spring elements can be used, so that between neighboring balls corresponding spring elements as spacers Elements act, such as helical compression springs, leg springs, Bending springs or spiral springs.

In another embodiment, elastomers can be used as spacing agents Feathers are used, for example from a foamed Plastic material or a rubber exist.

The subject matter of the present invention does not only result from the subject of the individual claims, but also from the Combination of the individual claims.

In the following the invention is based on several ways of execution illustrative drawings explained in more detail. Here go from the drawings and its description further features and advantages of the invention Invention.

All disclosed in the file, including the summary Information and features, especially those shown in the drawings spatial education are claimed as essential to the invention, insofar as they individually or in combination are new compared to the prior art.

Show it:

Fig. 1 schematically shows a first embodiment of a quick release device in two different working states;

FIG. 2 shows an embodiment modified compared to FIG. 1 with one on its spring ring;

Fig. 3 is a top view of various embodiments of spring washers and energy stores, which are suitable for biasing the piston

Fig. 4 shows a third embodiment of the mounting of rolling elements with a spring ring;

FIG. 5 shows the side view of the arrangement according to FIG. 4;

Fig. 6 is a plan view of various embodiments of gap holding means between the rolling elements;

Fig. 7 is a detail view partly in section of an embodiment according to Fig. 6.

In Fig. 1, a quick release device according to the invention is shown in the right half section in the locked state and in the left half section in the unlocked state.

A cylinder base 12 is detachably inserted in an essentially cup-shaped cylinder 1 and held by means of a locking ring 13 . Associated with the cylinder is a retaining ring 8 , which in turn is held in cylinder 1 via a locking ring 46 .

The retaining ring 8 forms the holder for a circumferential spring ring 15 and, in conjunction with side walls of the cylinder, it forms a pressure chamber 10 for the displaceably driven piston 4 .

By introducing a pressure medium into the connection 11 , this is introduced into the pressure chamber 10 via corresponding connecting channels and thus moves the piston 4 upwards into the unlocked position shown on the left in FIG. 1.

In this unlocked position, the retractable nipple 2 can be pulled out of the central receiving bore 47 .

The piston 4 also interacts with other locking balls 7 , which form a positive lock with the retractable nipple 2 .

The locking device 3 shown here thus acts twice, namely once via the rolling elements 5 , which exert the pull-in force on the pull-in nipple 2 in the pull-in direction and in this case bear the load on an associated bevel 21 of the pull-in nipple and at the same time rest on inclined surfaces (straight contact surface 23 and Support slope 22 ).

The piston 4 is otherwise held in its locked position by a force accumulator 6 , which in the exemplary embodiment shown consists of spring pins which are attached to the cylinder 1 in an evenly distributed manner in obliquely upwardly directed blind bores on the cylinder 1 in order to use their front, radially inward, Press the free ends onto the piston 4 .

According to the invention, the spring ring 15 , which forms the resilient ball retention for the rolling elements 5 , consists of a circumferential, self-contained retaining ring 14 , which forms a receiving space 20 in connection with assigned surfaces of the retaining ring 9 . The cranked lugs 19 of individual spring clips 16 engage in this receiving space.

The spring clips 16 are approximately U-shaped and the side legs 18 thus have the aforementioned extension 19 at their rear, free ends.

In the area of the center leg 17 , which connects the two side legs 18 , there is now approximately one rolling element 5 each, as shown in FIGS. 1 and 2.

In the unlocked state, the rolling element 5 is thus pressed obliquely radially inwards upward in the direction of arrow 26 against the underside of the piston 4 and held against falling out.

A further safeguard against falling out is formed by an axially downwardly extended nose 9 of the cylinder 1 , which forms the radial ball track for the locking ball 7 .

It is again pointed out that the locking device 3 shown here, which works with two locking elements 5 , 7 , is not necessary for a solution. All known locking devices, in particular also single-acting ones, can be used.

Instead of the rolling elements 5 designed as balls, for example, polygonal rolling elements, such as a hexagon nut or the like, can also be used as locking bodies.

The aforementioned locking balls 7 also engage in a circumferential annular groove 24 on the outer circumference of the retractable nipple 2 and rest there on an assigned radius 29 in a load-transmitting manner.

A further embodiment is shown in FIG. 2, from which it can be seen that a spring ring 25 can consist of individual lamellar spring plates 27 which are evenly distributed on the circumference of the spring ring 25 at a distance and separated from one another by slots 48 .

Here, the spring plates 27 are received in a retaining ring 28 , which in turn is seated in a receiving space 20 of the cylinder housing. The spring plates 27 can of course also be connected to one another on the foot side and can only be divided from one another by slots 48 , so that a circumferential plate ring results, the individual spring plates of which are separated from one another by slots 48 .

The rolling element 5 then lies on the respective upper, free ends of the spring plates 27 , wherein these contact surfaces can still be adapted to the shape of the rolling element.

The holder in the retaining ring 28 can also be designed as a crimp connection, so that the lamellar ring is supported in the retaining ring 28 via a crimp connection of the retaining ring.

FIG. 3 shows various embodiments of such ball retainers, the embodiment according to FIG. 2 being shown with individual spring plates 27 separated from one another between positions 32 and 33 .

The embodiment according to FIG. 1 is shown to the left of position 32 , from which it can be seen that an approximately U-shaped spring clip 16 serves as a ball bearing for the rolling element 5 . On the left next to the spring clip 16 , examples of different embodiments of energy stores 6 are also shown.

It is shown that individual spring pins 30 are arranged close to one another in the obliquely upwardly lying blind bores in the cylinder and act on the associated upper surfaces of the piston 4 .

Instead of a close-to-close arrangement, individual spring pins 30 a spaced apart from one another can also be provided.

These spring pins 30 a are then likewise arranged in mutually spaced, obliquely upwardly directed blind bores on the inside of the cylinder 1 .

As a replacement for the spring pins 30 , 30 a, corresponding spring plates 31 can also be used, which are also inserted in obliquely upward slits on the inside of the cylinder and act on the associated surface of the piston 4 .

There can also be a circumferential groove on the cylinder, in which there is a spring plate 31 , which forms individual spring plates.

Overall, this is intended to make it clear that with the resilient ball restraint, which is claimed in the context of the present invention, inter alia, as essential to the invention, the energy store 6 can also be designed in the same way and can have the same or similar spring or bending elements.

All of the spring elements and bending elements described below in connection with the ball restraint can therefore also be used as an energy store 6 .

FIG. 4 shows, in connection with FIG. 5 as a further embodiment, that the rolling elements 5 can each have a groove 36 approximately on the foot side, in which a flat spring 34 engages. This flat spring is preferably designed as a circlip and the spring ring 35 thus created forms a distance 38 on the end face which can be changed in a resilient manner.

In this way, all the rolling elements are threaded onto the spring ring 35 and have both a radial play in the arrow directions 37 and in the opposite direction. But you can also move in the circumferential direction on the flat spring 34 . FIGS. 6 and 7 show different embodiments for distance-maintaining means with which the balls have a variable distance in the circumferential direction, which is spring-loaded.

First, a helical compression spring 39 is shown, which is arranged in the space between two rolling elements 5 . All of the spacing means shown here are evenly distributed on the circumference, for the sake of simplicity only one different spacing means is shown in FIG. 6.

A spiral spring 40 according to FIG. 6 can be used as a further spacing means, two roughly curved spring loops 41 forming the bearing for the rolling elements 5 and the two spring loops 41 being connected to one another by a flexible center leg 42 .

With this means, too, the balls are distributed in a spring-loaded manner in their raceways on the piston 4 and on the retaining ring 8 .

As a further spacing, resilient means an elastomeric spring 43 is shown, the z. B. consists of a foamed plastic or a rubber material. Here, front gauntlets for storing the rolling elements 5 can be present on each end. Likewise, the elastomer spring 43 can also be made from a spray material.

In the further illustration according to FIG. 6, it is shown that facing blind holes 44 can also be arranged in the rolling elements 5 , in each of which a helical compression spring 39 engages.

This has the advantage that the blind bore 44 only partially engages the ball, but the sensitive core is not adversely affected thereby.

The further illustration in FIG. 6 shows that separate spacer pins can also be firmly anchored to the cylinder base 12 , between which a rolling element 5 is accommodated in each case. This spacer pins 45 can also be incorporated in the retaining ring 8 and z. B. be included in blind holes.

The two representations in FIG. 6 show that the spacer pins 45 can be arranged close to one another or spaced apart from one another.

FIG. 7 shows that the spacer pins are held obliquely in the associated receiving bores 49 of a retaining ring 8 or 28 .

Of course, it is also possible to use the previously described to mix and match different spacing agents combine, so that it is not necessary for a solution, always distributed around the circumference always arrange the same spacing means.

So while in the embodiment of FIGS. 1 and 2 loose, freely guided rolling elements 5 are arranged evenly distributed on the circumference and lie close to each other, the other embodiments show that fewer balls can be used, and then for this case spacing means are provided.

The advantage of freely guided rolling elements according to the exemplary embodiment according to FIGS. 1 and 2 is, moreover, that the same surfaces 21 , 22 , 23 are not always claimed at certain points, but that due to the play of the balls in the circumferential direction, the balls are always transportable. and rolling motion so that the same surfaces (with respect to a circumferential line) are not always used at certain points. This significantly increases the life of the entire fixture and the accuracy. This applies in particular to the retractable nipple 2 , because the same surfaces are not always loaded at certain points.

In the case of rolling elements that are held in rigid ball cages, this results namely, in the case of a longer period of operation pointing axially, line-shaped Tracks on the outer circumference of the retractable nipple, resulting in a high Wear is associated. So there are elongated recesses in the Retractable nipple and pressed into the piston races, what the Service life of the entire clamping device is severely limited.  

drawing Legend

1

cylinder

2

Retractable nipple

3

locking device

4

piston

5

rolling elements

6

power storage

7

check ball

8th

retaining ring

9

nose

10

pressure chamber

11

connection

12

cylinder base

13

circlip

14

retaining ring

15

spring washer

16

spring clip

17

middle leg

18

side leg

19

Approach (cranked)

20

accommodation space

21

slope

22

slope

23

contact surface

24

ring groove

25

spring washer

26

arrow

27

spring plate

28

retaining ring

29

radius

30

feather pen

30

a

31

spring plate

32

position

33

position

34

Flat spring (Seegerring)

35

spring washer

36

groove

37

arrow

38

distance

39

Helical compression spring

40

bending spring

41

spring loop

42

middle leg

43

elastomer spring

44

blind hole

45

peg

46

circlip

47

location hole

48

slot

49

mounting holes

Claims (14)

1.Quick-clamping device for clamping a retractable nipple in a cylinder with a simplified structure with a piston which is displaceably driven in at least one direction in the cylinder under the action of a pressure medium and which is acted upon in the other direction by an energy accumulator and interacts with a locking device which works out Rolling bodies exist which, in the locking position, engage in tracks arranged on the outer circumference of the retractable nipple, characterized in that the rolling bodies ( 5 ) are guided without a cage and are spaced apart on circumferential ball tracks of the piston ( 4 ) and the cylinder ( 1 ) and through on the bottom side Rest on a spring means are secured against falling radially inward. 2. Quick release device according to claim 1, characterized in that the spring means is designed as a spring ring ( 15 , 25 , 35 ). 3. quick release device according to claim 2, characterized in that the spring ring ( 15 ) consists of individual separate and spaced apart spring clips ( 16 ), wherein each ball rests on an associated spring clip ( 16 ) and 4. quick release device according to claim 3, characterized in that the spring clip ( 16 ) are arranged close to each other distributed close to the circumference of a spring ring. 5. Quick-release device according to one of claims 1 to 4, characterized in that the spring clip is designed as a U-shaped spring loop ( 41 ). 6. Quick-release device according to one of claims 1 to 5, characterized characterized in that the spring clip consists of individual pin springs.   7. Quick release device according to one of claims 1 to 4, characterized characterized that the spring clip consists of individual spring plates. 8. quick release device according to one of claims 1 to 4, characterized characterized in that the spring clip consists of a brush-like ring. 9. quick release device according to one of claims 1 to 4, characterized characterized that the spring clip from cuff-shaped spring cuffs consists. 10. Quick release device according to one of claims 1 to 9, characterized in that grooves ( 36 ) are milled into the lateral surface of the rolling elements, and each groove is penetrated by part of a spring ring ( 34 , 35 ). 11.Quick-clamping device for clamping a retractable nipple in a cylinder with a simplified structure with a piston which is displaceably driven in at least one direction in the cylinder under the action of a pressure medium and which is acted upon in the other direction by an energy accumulator and interacts with a locking device which works out Rolling bodies which engage in the locking position on tracks arranged on the outer circumference of the retractable nipple, characterized in that the rolling bodies ( 5 ) are arranged evenly distributed over the circumference by means of spacers ( 39 , 40 , 43 , 45 ). 12. Quick release device according to claim 11, characterized in that the spacing means are designed as spring elements. 13. Quick release device according to one of claims 1 to 12, characterized in that the retractable nipple ( 2 ) is assigned a double locking device. 14. Quick-release device according to one of claims 1 to 13, characterized in that the piston ( 4 ) is held in its locked position by an energy accumulator ( 6 ) which consists of spring pins ( 30 , 30 a) or spring plates ( 31 ), which are attached to the cylinder ( 1 ) evenly distributed over the circumference in obliquely upward blind holes, and press with their front, radially inward, free ends onto the piston ( 4 ).