KR20200036758A - Doffer gripper with a two-part housing - Google Patents

Abstract

Retaining element 2 with a pneumatically operable membrane 5 as a clamping element for the bobbin or bobbin tube 3 arranged on the outer wall 12 and the inner wall 4 and the inner wall 4 ) And a fastener fixing element (7), the gripper (1) for gripping the bobbin or bobbin tube (3), where the membrane (5) can be actuated by compressed air through the air duct (16). Is described.
Here the retaining element 2 is arranged between the anchoring element 11 and the fastener anchoring element 7, wherein the anchoring element 11 partially surrounds the outer wall 12 of the retaining element 2 It is connected to the fastener fixing element (7). According to the invention, the membrane 5 is physically coupled to the upper and / or lower edges of the holding element 2, which may have a shoulder-like shape. The invention also relates to a holding element 2 and a corresponding doffer with a gripper 1.

Description

DOFFER GRIPPER WITH A TWO-PART HOUSING}

The present invention relates to a gripper for gripping a bobbin or bobbin tube, and a holding element for such a gripper according to the preamble of the independent claim. It also relates to a doffer having a doffer beam with at least one gripper according to the invention, and a ring spinning machine having such a doffer.

For several types of spinning machines, especially ring spinning machines, a plurality of cobbs and / or bobbins that are already wound are removed together from the spinning stations of the spinning machine during a bobbin change operation and replaced with an empty bobbin tube. To this end, the spinning machine has a doffer device with a doffer beam mounted on the spinning machine so that it can be moved by a scissor mechanism. A plurality of grippers and / or doffer grippers, in turn, are provided on the doffer beam to enable the bobbins and / or the empty bobbin tubes to be gripped together to remove and / or attach them. The individual grippers are preferably pneumatically operable and include a clamp element in the form of a membrane, which clamp element rests on a bobbin or bobbin tube, suitable for manipulation with compressed air, and then on a bobbin or bobbin. The tube is gripped by introducing compressed air. Ducts carrying compressed air are provided in the doffer beams, so that compressed air is supplied through feeder lines for each one of the individual films of the grippers, and compressed air can be supplied to the individual grippers.

A similarly designed gripper is described in CN2873813Y. The gripper has a cylindrical retaining element for receiving the bobbin or bobbin tube here. A clamp element in the form of a rubber membrane, adjustable by a pneumatic device, is provided on the inner wall of the retaining element. In this membrane, it is possible to grip the outside of the end region of the bobbin or bobbin tube inserted into the interior of the holding element. The membrane is fixed on the holding element by two stoppers arranged on the top and bottom surfaces of the holding element in the direction of the longitudinal axis. The two stoppers are clipped to the retaining element using a snap connection. For attachment to the doffer beam, the gripper includes a fastening element. The fastener fastening element is permanently connected to the retaining element and has an air duct for compressed air transported to the membrane. The fastener retaining element has a hook on its top surface and an elastic retaining strap on its bottom surface. The gripper is secured on the receptacle by a hook, and secured to the locking groove on the doffer beam by an elastic retaining strap. Grippers with similar designs are disclosed in EP0303877A1. In contrast to the gripper described above, the fastener fixing element of this gripper has an elastic retaining strap on its bottom surface and its top surface. Using two elastic retaining straps, the gripper can be removed and releasably attachable to the doffer beam in two parallel locking grooves. The locking groove makes it possible to fasten a plurality of individual grippers along the doffer beam.

When changing the bobbin or bobbin tube, the membrane is acted by compressed air through the air duct. Thus, the membrane contracts in the retaining element and grips the bobbin or bobbin tube from the outside in its end region. To release the bobbin or bobbin tube within the retaining element, the membrane is released by removing compressed air. The membrane wears out after a certain period of operation due to the friction of the membrane on the bobbin or bobbin tube, and the release of the membrane and constant fluctuation of the load. This wear is manifested by the fact that the membrane becomes porous and leaking spots are formed. As a result, reliable replacement of bobbins or bobbin tubes is no longer guaranteed. Therefore, it is necessary to replace the worn film with a new film after a certain operating time.

One important drawback of the grippers described herein is that the replacement of new and worn films is very complex to implement. In order to replace the membrane, the gripper must first be removed from the doffer beam by the operator. To do this, in the case of the gripper disclosed in CN2873813Y, the hook is released from the receptacle of the doffer beam, and the elastic retaining strap slides out of the locking groove, or in the case of the gripper disclosed in EP0303877A1 Thus, the two elastic retaining straps slide out of the two parallel locking grooves. On the outside of the doffer device, the top cap and the bottom cap are then released from the holding element. The worn film is then released from the holding element and replaced with a new film. The new film is then fixed again on the holding element by a stopper in the direction of the longitudinal axis of the holding element, and the gripper is mounted on the doffer beam. Due to the gripper design, it is very complicated to replace the worn film because the entire gripper has to be removed from the doffer beam. Therefore, the replacement of the membrane is associated with the long downtime of the spinning machine. Moreover, there is unnecessary wear on the gripper's elastic retaining strap, due to the frequency with which the gripper is dismounted and mounted from the doffer beam. As a result, a proper clamping effect of the elastic retaining strap in the locking groove on the doffer beam is not guaranteed.

To avoid this drawback, WO2016071789 discloses a gripper for gripping a bobbin or bobbin tube with a cylindrical retaining element having a longitudinal axis and a fastener fixing element, wherein the retaining element has an inner wall and an outer wall, air A pneumatically operable clamping element that can be actuated by compressed air through the duct is provided on the inner wall. In order to simplify the gripper design, it is then proposed that the retaining element must be retained in the fastener retaining element using the retaining element, wherein the retaining element partially surrounds the outer wall of the retaining element. The gripper is made of plastic and has a cylindrical retaining element or bobbin or bobbin tube. The retaining element has an inner wall, and on the inner wall there is a pneumatically adjustable clamping element in the form of a rubber membrane. To seal the membrane against the retaining element, a sealing ring is provided between the anchor element and the fastening element and the fastening element on the upper and lower ends of the retaining element.

The present invention is based on the object of making a gripper for gripping a bobbin or bobbin tube with a retaining element characterized by a better sealing effect than known prior art grippers.

The invention is also based on the object of making a gripper for gripping a bobbin or bobbin tube with a retaining element characterized by a shorter gripping time of the doffer.

The present invention is also based on the object of making a gripper for gripping a bobbin or bobbin tube with retaining elements characterized by simplified production.

This object is achieved by the independent claims, wherein the dependent claims provide advantageous embodiments.

In particular, this object is achieved by a gripper for gripping the retaining element and the bobbin or bobbin tube according to the preamble of the independent claim, and the membrane is connected in such a way that it is physically coupled to the upper and / or lower edge of the retaining element. It is characterized by.

The retaining element advantageously has an upper and / or lower shoulder, such as an edge, where the membrane is physically coupled to the upper and / or lower shoulder. Alternatively, the membrane can be physically coupled to only one lower shoulder, such as the edge of the retaining element. The cover is located on the upper end of the retaining element and a membrane is passed around it. The edge of the cover slightly overlaps the edge of the retaining element. Before welding to the lower shoulder, the membrane is tensioned while being pulled downward between the cover and the retaining element, so that the cover is compressed against the retaining element. This example not only results in simple production, but also leads to good sealing of the membrane. The retaining elements can be prefabricated and can be easily replaced in this way.

The physical bonding between the membrane and the holding element can preferably occur via adhesive bonding, welding, vulcanization or some other suitable method.

The groove can advantageously be formed on the fastener fixing element or the safety element by means of the projection, so that the shoulder of the retaining element can be inserted into the groove. Additionally, the cover can form the upper edge of the retaining element together with the upper edge of the fastening element and the upper edge of the fastening element. The aforementioned edges are bent inward for this purpose. It is defined between the fastener fixing element and the safety element so that reliable maintenance can be ensured in this way.

The retaining element can advantageously be designed to be cylindrical or to have a bottom-up taper. The air duct can advantageously be provided on the outer wall and can be directed upward along the outer wall. In this way, the retaining element can be used in various ways in various doffer grippers.

In order to replace the membrane, it is advantageously possible to leave the gripper on the doffer beam and remove the retaining element from the fastener fixing element. To do this, it is only necessary to remove the fixing element from the fastener fixing element. The retaining element can then be removed as one unit and replaced as a whole. Another advantage of the retaining element is that it is compactly constructed as a unit and features a physically coupled connection due to a better sealing effect on the prior art design of the retaining element. Due to the conical embodiment of the retaining element, reliable holding of the bobbin or bobbin tube and shorter gripping time of the doffer can be advantageously achieved.

The invention also relates to a doffer having a doffer beam with at least one gripper according to the invention, and also to a spinning machine having such a doffer.

Additional advantages of the invention are described in the examples of the following embodiments.
1 shows a perspective view of a gripper according to the invention.
2 shows a longitudinal cross-section of the gripper according to FIG. 1.
3 shows a perspective view of a first embodiment of a retaining element according to the invention.
4 shows a longitudinal section through the holding element according to FIG. 3.
5 shows a perspective view through a second embodiment of the retaining element according to the invention.
When the same members are shown in different drawings, they have the same reference number.

1 shows a perspective view of a grip 1 according to the invention, and FIG. 2 shows a longitudinal cross-section of the grip according to FIG. 1. The grip 1 is made of plastic and has a retaining element 2 tapered towards the top for the bobbin or bobbin tube 3. The retaining element 2 has an inner wall 4, which is provided with a pneumatically adjustable clamping element in the form of a membrane 5 made of rubber. In the membrane 5, it is possible to grip the end region of the bobbin or bobbin tube 3 inserted inside the holding element 2 from the outside. The membrane 5 is adjusted in the direction of the two-way arrow 6 using a pneumatic device. The gripper 1 is known from publication WO2016059496 but has a fastener fixing element 7 for fastening the gripper 1 on a doffer beam (not shown).

Since the fastener fixing element 7 has two elastic retaining straps 8 arranged at a constant distance from each other, and one rigid support element arranged between the elastic retaining straps, the two elastic retaining straps 8 Is connected to the fastener fastening element 7 at the first end 9 and is respectively positioned in a seating position using at least one spring element at the second free end 10. The gripper 1 can be unlocked with the second free end 10 and can be releasably mounted on the doffer beam. It is provided that the at least one spring element is designed in one piece with a rigid support element and free ends 9 and 10 of the individual elastic retaining straps 8.

The holding element 2 is held on the fastener fixing element 7 using a fixing element 11. The fixing element 11 surrounds at least 180 ° of the outer wall 12 of the holding element 2. The fixing element 11 thus represents a part of the housing of the gripper 1 in addition to the fastener fixing element 7. The holding element 2 is secured on the fastener fixing element 7 across the longitudinal axis 13 using a fixing element 11. The fixing element 11 is releasably connected to the fastener fixing element 7 using a snap connection. The snap connection, the fastener fixing element 7 is designed to have risers, and the fixing element 11 has two lateral straps 14 with recesses, the recesses surrounding the risers And / or the risers in the recesses are engaged in a manner known, for example, from FIG. 5 of WO2016071789.

The fastener fixing element 7 is permanently connected to the holding element 2 and has an air duct 16 for supply of compressed air towards the membrane 5. The air duct 16 is connected to a compressed air line extending longitudinally on the doffer beam. The air duct 16 is sealed against the doffer beam by a first sealing element 17 provided on the fastener fixing element 7. The sealing element 17 is designed like a tube made of rubber. The fastener fixing element 7 also has a second sealing element 18 which seals the gripper 1 against a compressed air signal line which also extends in the longitudinal direction on the doffer beam.

The air duct 16 is permanently connected to the outer wall 12 of the retaining element 2, ie the retaining element 2 and the air duct 16 are designed in one piece. The air duct 16 has an annular shoulder 20 on its outer surface 19. The shoulder 19 is made of elastic plastic that extends over 8 mm of the length of the air duct 16. The shoulder 19 is connected to the air duct 16 in a one-piece shape. The fastener fastening element 11 has a receptacle 21 for the air duct 12. The receptacle 21 is designed to be cylindrical, and extends beyond the length of the air duct 16. The holding element 2 is loosely connected to the fastener fixing element 7 through the shoulder 20 of the air duct 16. At its first end 22, the sealing element 17 is in contact with the annular shoulder 20 of the air duct 16. At its second end 23, the sealing element 13 seals the air duct 12 against the compressed air line on the doffer beam. When compressed air acts on the membrane 5, the air duct 16 expands radially in the receptacle 20 in the radial direction. In this way, the shoulder 20 is compressed against the fastener fastening element 11 and seals the air duct 16 against the fastener fastening element 7.

3 shows a perspective view of the retaining element 2 according to the invention, and FIG. 4 shows a longitudinal cross-section of the retaining element 2 according to FIG. 3. The holding element 2 is configured to have a step in the middle, and in the example shown here, it is tapered toward the top. The holding element 2 is preferably made of injection molding. The shoulder 24 is provided on the lower edge of the retaining element 2. Membrane 5 may be glued, welded or vulcanized to the bottom surface of shoulder 24, or may be physically bonded thereto in some other suitable manner. The plastic laser welding method can preferably be used for this purpose. Thus, the retaining element 2 can be made of a laser absorbing material such as polyamide 6 [nylon 6], while the film 5 is made of a laser permeable material such as a thermoplastic polyurethane (TPU). Since the upper edge of the holding element 5 has a cover 25, the edge of the cover 25 slightly overlaps the edge of the holding element 2, and the film 5 covers the holding element 2 between the holding elements 2 (25). ) It is supposed to pass around. Before welding, gluing or other types of bonding at the lower edge 24, the film 5 is tensioned while being pulled downward between the holding element 2 and the cover 25 for a good sealing effect, so that the cover ( 25) is compressed against the retaining element 2. Thereafter, the film 5 is bonded to the shoulder 24 by adhesion or welding.

The retaining element 2 designed in this way is introduced between the fastener fixing element 7 and the fixing element 11 so that the annular shoulder 20 is inserted into the receptacle 21 (see Fig. 2). For the purpose of fixing, there is an outer circumferential rib 26 on the lower ends of the fastener fixing element 7 and the safety element 11 as a whole. The shoulder 24 of the retaining element 2 is inserted into the groove under the rib 26. At the upper end, the upper edge 27 of the fastening element 11 and the upper edge 28 of the fastener fixing element 7 together with the cover 25 form an upper fixing portion. Thus, the aforementioned edges 27, 28 are positioned on the retaining element 2 right next to the cover 25, bent inward, and joined in a frame-fitting manner (see Fig. 1).

The retaining element 2 in the embodiment shown here is designed to be tapered with one step, but may have several other shapes. In addition, it may have a bottom-up taper without a step, or may be designed as a cylinder (not shown). According to another embodiment (not shown here), it is also conceivable to provide a shoulder on the upper end, and weld the membrane 5 to the upper shoulder as well.

5 shows a perspective view of a second embodiment of the retaining element 2 according to the invention. The retaining element 2 has the same design as the retaining element 2 shown in Figs. 3 and 4, but has a connecting stopper protruding beyond the cover 25 and an upwardly directed air duct 29. Has been properly connected to the compressed air line here. The air duct 29 is part of the upper section of the outer wall 12 and is integrated into the outer wall. This embodiment is suitable for a devil gripper such as is known, for example, in FIGS. 2A, B or 5 of WO2017085588.

In order to replace the membrane 5, it is also possible to leave the gripper 1 on the doffer beam and remove the retaining element 2 from the fastener fixing element 7. To do this, the fixing element 11 is removed from the fastener fixing element 7. The retaining element can then be removed as a unit and can be easily replaced. This minimizes the downtime of the spinning machine during membrane 5 replacement. Furthermore, any unnecessary wear on the elastic retaining strip 8 on the fastener retaining element 7 is prevented, since only the retaining element 2 needs to be removed from the gripper 1. This ensures a sufficient clamping effect of the elastic retaining strips 8 on the doffer beam. Another advantage of the retaining element 2 is that it is designed as a compact unit and features a physically coupled connection with a better sealing effect compared to retaining elements designed according to the prior art. Due to the conical shape of the retaining element, a more reliable retention of the bobbin or bobbin tube 3 and a shorter gripping time of the doffer can also be advantageously achieved.

1 gripper
2 retaining elements
3 bobbin tube
4 inner wall
5 Act
6 2-way arrows
7 Fastener fixing elements
8 retaining strap
9 first end
10 free ends
11 fixed elements
12 outer wall
13 longitudinal axis
14 Strap
16 air ducts
17 sealing elements
18 sealing elements
19 outer surface
20 annular shoulder
21 receptacles
22 First end of the sealing element 17
23 Second end of the sealing element 17
24 shoulder
25 ribs
26 covers
27 Upper edge of fixing element (11)
28 Upper edge of fastener fixing element (7)
29 air duct

Claims (15)

As a gripper (1) for gripping the bobbin or bobbin tube (3),
Fastener fixing elements 7;
It has a pneumatically operable membrane 5 as a clamping element for holding the outer wall 12 and the inner wall 4 and the bobbin or bobbin tube 3 arranged on the inner wall 4, A retaining element 2 through which the membrane can be acted upon by compressed air through the air duct 16;
Equipped with,
The holding element 2 is arranged between the fixing element 11 and the fastener fixing element 7,
The fixing element 11 is connected to the fastener fixing element 7 while partially surrounding the outer wall 12 of the holding element 2,
The gripper 1, characterized in that the membrane 5 is connected to the upper and / or lower edge of the retaining element 2 by physically joining the upper and / or lower edge of the retaining element 2 together. According to claim 1,
The retaining element 2 has an upper and / or lower shoulder 24, such as an edge,
The gripper 1, characterized in that the membrane 5 is connected to the upper and / or lower shoulder 24 by physically bonding, preferably by welding, vulcanizing or bonding. The method of claim 1 or 2,
The membrane 5 is physically coupled to the lower edge of its shoulder 24 of the retaining element 2,
A gripper (1) characterized in that there is a cover (25) on the upper end of the retaining element (2), with a membrane (5) passing around it. The method of claim 2 or 3,
A groove into which the shoulder 24 can be inserted is provided on the fixing element 11 as well as a fastener fixing element 7 into which the shoulder 24 can be inserted,
The cover 25 together with the upper edge 27 of the fastening element 11 and the upper edge 28 of the fastener fixing element 7 form the upper fixing portion of the holding element 2, the gripper 1 characterized in that . The method according to any one of claims 1 to 4,
The gripper 1, characterized in that the holding element 2 is made of a laser absorbing material, and the film 5 is made of a laser transmitting material. The method according to any one of claims 1 to 5,
The holding element (2) is a gripper (1), characterized in that it is designed to be cylindrical or to be tapered toward the top. The method according to any one of claims 1 to 6,
The air ducts (16, 29) are arranged on the side of the outer wall (12), or the gripper (1) characterized in that it runs upward on the outer wall (12). A retaining element (2) for the gripper (1) according to any one of the preceding claims,
The retaining element 2 is a clamping element for gripping the outer wall 12 and the inner wall 4 and the bobbin or bobbin tube 3 arranged on the inner wall 4, which is a pneumatically operable membrane ( 5), the compressed air can act on the membrane through the air duct,
The retaining element 2, characterized in that the membrane 5 is connected by physically engaging the upper and / or lower edge of the retaining element 2, The method of claim 8,
The retaining element 2 has an upper and / or lower shoulder 24, such as an edge,
The retaining element 2, characterized in that the membrane 5 is connected to the upper and / or lower shoulder 24 in a physically coupled manner, preferably by welding, vulcanizing or bonding, The method of claim 8 or 9,
The membrane 5 is physically coupled to the shoulder 24 or the lower edge of the retaining element 2,
The retaining element 2, characterized in that the cover 25, through which the membrane 5 passes, is located on the upper end of the retaining element 2, The method according to any one of claims 7 to 10,
The holding element 2 is designed to be cylindrical, or is designed to be tapered toward the top, characterized in that the holding element 2, The method according to any one of claims 7 to 11,
The holding elements 2, characterized in that the air ducts 16, 29 are arranged on the side of the outer wall 12, or are passed upward along the outer wall 12, The method according to any one of claims 7 to 12,
The holding element 2 is produced from a laser-absorbing material by an injection molding method, the holding element 2 being characterized by A doffer, characterized in that it comprises a doffer beam with at least one gripper (1) for gripping a bobbin or bobbin tube (3) according to any of the preceding claims. A ring spinning machine characterized in that it has a doffer according to claim 1.

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