CN217941399U

CN217941399U - Band steel coiling-aid device capable of reliably pre-bending band head

Info

Publication number: CN217941399U
Application number: CN202221378461.9U
Authority: CN
Inventors: 王子标; 杨国良; 周云根
Original assignee: Wisdri Engineering and Research Incorporation Ltd
Current assignee: Wisdri Engineering and Research Incorporation Ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-12-02
Anticipated expiration: 2032-05-31

Abstract

The utility model relates to a belted steel that can reliably preflex tape head helps a roll device, including helping the book frame, help a roll frame to have the C type that can accept the reel and accomodate the groove, help to be equipped with belt operation roller system on the book frame, the coiling helps a roll belt and supplementary roll mechanism that helps on belt operation roller system, supplementary roll mechanism that helps is including helping a roll roller seat, arrange a plurality of help on helping a roll roller seat roll compression roller and be used for the drive to help roll roller seat activity in order to change the compression roller drive unit who helps roll interval between compression roller and the reel, help roll roller seat hinge connect on accomodating the groove cell body and the hinge axial direction is on a parallel with helping roll compression roller axial. The auxiliary winding roller seat can swing relative to the hinge shaft, and partial auxiliary winding rollers can pre-bend the head of the strip steel no matter winding up or winding down; in addition, the distance between the plurality of the wrapper rollers and the winding drum is uniform, the pressure is balanced, each wrapper roller is adaptive to the action force fluctuation condition when the strip steel is reeled, the reeling process is well matched, and a good reeling effect is realized.

Description

Band steel coiling-aid device capable of reliably pre-bending band head

Technical Field

The utility model belongs to the technical field of belted steel production, concretely relates to belted steel that can reliable preflex tape head helps a package to put.

Background

The high-strength plate and the medium plate are widely applied to the fields of the automobile industry, the machine manufacturing industry, hardware fittings, stamping parts with various shapes and the like. With the further expansion of the market demand of high-strength thick plates in China, a plurality of special high-strength thick plate strip steel processing units are built and established at present, and the coiling of the strip heads of the high-strength thick plates becomes a great problem of the units. At present, the coiling of the medium plate adopts a jaw form, the generated residual tape head can not be pasted on the inner diameter of the coiled material, adverse effects are brought to packaging and downstream uncoiling production, and the problem can be solved by adopting a belt to assist the coiling to replace the jaw coiling. The Chinese patent application CN201911240780.6 discloses a strip steel coiling assisting device, which is characterized in that an auxiliary coiling assisting mechanism is added on the basis of the existing belt coiling assisting device, and a strip head can be pre-bent by matching a coiling assisting press roller with a winding drum; however, in the scheme, only one of the plurality of auxiliary winding rollers is tightly pressed on the strip steel, and the other auxiliary winding rollers are mainly used for forming the pre-bending channel in a matched mode, so that the using effect is poor, and the pre-bending channel is fixed in one direction and cannot be reversed, so that the winding requirements in the upper direction and the lower direction are difficult to meet.

SUMMERY OF THE UTILITY MODEL

The utility model relates to a band steel coiling assisting device capable of reliably pre-bending a band head, which can at least solve part of the defects of the prior art.

The utility model relates to a belted steel that can reliably prebend tape head helps a roll device, including helping the book frame, help a roll frame to have the C type that can accept the reel and accomodate the groove, help to be equipped with belt operation roller system and convolute on the book frame help a roll belt on the belt operation roller system, help still to be equipped with supplementary book mechanism of helping on the book frame, supplementary help a roll mechanism including helping a roll roller seat, arrange in help a plurality of on the roll roller seat help a roll compression roller and be used for the drive help roll roller seat activity in order to change the compression roller drive unit who helps roll interval between compression roller and the reel, help roll roller seat hinge connect on accomodating the groove cell body and hinge axial direction is on a parallel with help roll compression roller axial.

In one embodiment, the press roll driving unit is connected to the tail of the wrapper roll seat along the running direction of the strip steel.

As one embodiment, the press roller driving unit employs an air cylinder, a hydraulic cylinder, or an electric push rod.

In one embodiment, the wrapper rollers on the wrapper roller seat are sequentially arranged at intervals along the circumferential direction of the C-shape of the accommodating groove to form a roller row, and the guide surface of the roller row is an arc surface.

In one embodiment, the auxiliary winding assisting mechanisms have a plurality of sets, and each auxiliary winding assisting mechanism is sequentially arranged along the circumferential direction of the C-shape of the accommodating groove.

As one embodiment, two ends of the notch of the accommodating groove are respectively provided with a holding arm mechanism for cooperating with the winding drum for winding.

As one embodiment, the arm embracing mechanism comprises an arm embracing driving unit and an arm embracing frame rotatably mounted on the auxiliary winding frame, and the arm embracing frame is connected with the arm embracing driving unit so as to drive the steering roller to swing to an embracing state close to a winding drum and an opening state far away from the winding drum.

As one embodiment, a pressing plate is further installed on the arm holding frame, and the installation position of the pressing plate satisfies the following conditions: in the clasping state, the pressing plate is close to the winding drum and is matched with the winding drum to form a tape head guide channel.

In one embodiment, the belt running roller system includes a plurality of supporting rollers, at least one tension roller, and a turning roller mounted at the free end of the arm-clasping mechanism, wherein each of the supporting rollers and each of the tension rollers are mounted on the winding frame and located outside the accommodating groove.

The utility model discloses following beneficial effect has at least:

in the utility model, the roll-assisting roller seat can swing relative to the hinge shaft, and no matter the roll is taken up or taken down, partial roll-assisting pressing rollers can firstly contact the roll-assisting belt to pre-bend the head of the strip steel; the counter-acting force of the wrapper belt has the tendency of pushing the wrapper roller seat to rotate around the hinge shaft, and the uniform distance and the balanced pressure between the plurality of wrapper rollers on the wrapper roller seat and the winding drum are realized through the coordination of the roller driving unit and the counter-acting force of the wrapper belt, so that each wrapper roller is adaptive to the action force fluctuation condition when the strip steel is reeled, the reeling process is well matched, and the better reeling effect is realized.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of a strip steel rolling aid device provided by an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a strip steel rolling assisting module provided by the embodiment of the present invention;

fig. 3 is a schematic structural view of an auxiliary winding mechanism provided in an embodiment of the present invention;

fig. 4 is a schematic view of a coiling state of the strip steel coiling assisting device provided by the embodiment of the utility model.

Detailed Description

The technical solutions in the embodiments of the present invention are described below clearly and completely, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

As shown in fig. 1-4, an embodiment of the present invention provides a band steel roll-assisting device, which includes a roll-assisting frame 21, the roll-assisting frame 21 has a storage groove capable of storing a winding drum 3, a belt running roller system and a roll-assisting belt 22 wound on the belt running roller system are disposed on the roll-assisting frame 21, an auxiliary roll-assisting mechanism is further disposed on the roll-assisting frame 21, and the auxiliary roll-assisting mechanism includes a roll-assisting roller seat 242, a plurality of roll-assisting rollers 241 disposed on the roll-assisting roller seat 242, and a roller driving unit for driving the roll-assisting roller seat 242 to move so as to change a distance between the roll-assisting rollers 241 and the winding drum 3.

It is understood that the axial direction of the wrapper roller 241 is parallel to the axial direction of the winding drum 3, and each wrapper roller 241 is used for contacting the wrapper belt 22, therefore, each wrapper roller 241 is preferably arranged along the bottom of the storage groove, generally, the storage groove is a C-shaped groove, and each wrapper roller 241 is arranged along the C-shaped circumference of the storage groove, that is, along the strip winding direction. In one embodiment, the rolling-assistant frame 21 includes two structural plates, each of the two structural plates is provided with a C-shaped groove, and the two groove plates are parallel and opposite and spaced to form the C-shaped accommodating groove on the rolling-assistant frame 21; the wrapper roller seat 242 may be disposed between two structural panels.

By arranging the auxiliary rolling-assistant mechanism 24, the rolling-assistant press roller 241 can apply pressure to the head of the strip steel between the rolling-assistant belt 22 and the winding drum 3, so as to achieve the effect of pre-bending the head of the strip steel, make the head of the strip steel better fit on the winding drum 3 and occluded by the rolling-assistant belt 22 and the winding drum 3, improve the rolling effect and efficiency of the strip steel, avoid the abrasion and scratch of the head of the strip steel on the rolling-assistant belt 22, and better solve the problem that the high-strength thick plate in the prior art is difficult to roll. In addition, under the cooperation of the auxiliary winding press rolls 241, the winding tension can be increased, so that the strip steel can be wound on the winding drum 3 better.

In one embodiment, the platen roller driving unit 243 may be a linear driving unit for driving the wrapper roller holder 242 to move linearly to approach or separate from the winding drum 3, and accordingly, the platen roller driving unit 243 may employ a linear driving device such as an air cylinder, a hydraulic cylinder, or the like.

In another embodiment, as shown in fig. 3, the wrapper roller holder 242 is hinged to the receiving groove body and the hinge shaft is axially parallel to the wrapper roller axial direction. In this solution, the wrapper roller holder 242 can swing with respect to the hinge shaft, and whether it is an upper winding or a lower winding, part of the wrapper roller 241 is made to contact the wrapper belt 22 first to pre-bend the strip steel head; defining the auxiliary winding press roll 241 on the auxiliary winding roll seat 242, which contacts the auxiliary winding belt 22 first, as a pre-bending press roll, in this case, if the output end of the press roll driving unit 243 is connected to the side of the auxiliary winding roll seat 242, which is far away from the pre-bending press roll, according to the lever principle, the pre-bending pressure on the head of the strip steel can be effectively increased, the pre-bending effect is improved, and the energy-saving effect can also be achieved; in addition, the reaction force of the wrapper belt 22 tends to push the wrapper roller holder 242 to rotate around the hinge shaft, and the uniform distance and pressure balance between the plurality of wrapper rollers 241 on the wrapper roller holder 242 and the winding drum 3 are realized through the coordination of the roller driving unit 243 and the reaction force of the wrapper belt 22, so that each wrapper roller 241 is adaptive to the action force fluctuation condition during the strip steel winding, better matches the winding process, and realizes better winding effect. The platen roller driving unit 243 may also employ a linear driving device such as an air cylinder, a hydraulic cylinder, or the like, accordingly.

The wrapper rollers 241 on the wrapper roller seat 242 are sequentially arranged at intervals to form a roller row, the guide surface of the roller row is an arc-shaped surface, that is, the front end of each wrapper roller 241 is located on the same arc-shaped surface, and the curvature of the arc-shaped surface is preferably the same as the C-shaped curvature of the C-shaped groove.

Further preferably, as shown in fig. 1 to fig. 3, the auxiliary rolling-up mechanisms 24 have a plurality of groups and are sequentially arranged along the circumferential direction of the accommodating groove body, that is, along the circumferential direction of the C-shape of the accommodating groove or along the strip coiling direction. By arranging a plurality of groups of auxiliary rolling-assisting mechanisms 24, each auxiliary rolling-assisting mechanism 24 is independently controlled, on one hand, the head of the strip steel can be sequentially pre-bent, the pre-bending effect of the head of the strip steel is ensured, and the strip steel 4 can be better wound on the winding drum 3; on the other hand, the purpose of improving the coiling efficiency and saving energy can be achieved, specifically, when the head of the strip steel reaches the second group of auxiliary coiling mechanisms 24, the second group of auxiliary coiling mechanisms 24 further pre-bends the head of the strip steel, the acting force of the compression roller driving unit 243 of the first group of auxiliary coiling mechanisms 24 can be correspondingly reduced, and besides the effect of realizing uniform distance and pressure balance between the plurality of coiling assisting compression rollers 241 on the coiling assisting roller seat 242 and the coiling drum 3, the running smoothness of the strip steel can be improved, the coiling efficiency is correspondingly improved, and the energy is saved. In addition, when the strip steel coiling assisting device can be matched with an upper coiling operation and a lower coiling operation, the strip steel head processing requirements during the upper coiling operation and the lower coiling operation can be better met by arranging a plurality of groups of auxiliary coiling assisting mechanisms 24.

In this embodiment, two sets of auxiliary wrapper mechanisms 24 are provided.

Preferably, as shown in fig. 1, 2 and 4, arm holding mechanisms 23 for cooperating with the winding drum 3 to wind are respectively disposed at two ends of the notch of the receiving groove. The two groups of arm-holding mechanisms 23 are respectively used for the upper coiling operation and the lower coiling operation, so that the strip steel coiling assisting device can meet the operation requirement of the upper coiling and the lower coiling.

Further, the winding assisting frame 21 further comprises a belt running roller system arranged on the winding assisting frame 21 and a winding assisting belt 22 constrained by the belt running roller system in a tensioning manner. The wrapper belt 22 is wrapped around the winding drum 3 at a certain wrap angle on the winding drum 3, so that a strip V-shaped inlet is formed between the wrapper belt 22 and the winding drum 3 for engaging the head of the strip 4 to facilitate the winding of the strip.

The arm embracing mechanism 23 is mainly used for assisting the winding drum 3 to wind the strip steel 4, and in one embodiment, as shown in fig. 1 and 2, the arm embracing mechanism 23 comprises an arm embracing driving unit and an arm embracing frame rotatably mounted on the winding assisting frame 21, and the arm embracing frame is connected with the arm embracing driving unit so as to drive the steering roll to swing to an embracing state close to the winding drum 3 and an opening state far away from the winding drum 3. The arm-embracing driving unit can adopt driving devices such as a hydraulic cylinder, an air cylinder and the like, a shell of the arm-embracing driving unit is preferably hinged on the coil assisting frame 21, an output end of the arm-embracing driving unit is preferably hinged with the arm-embracing frame, and the arm-embracing driving unit can realize that the arm-embracing frame swings in a vertical plane to be close to or far away from the winding drum 3 (namely, can be switched between a embracing state and an opening state). In actual operation, the swing angle of the arm holding frame can be controlled by the arm holding driving unit to control the wrap angle of the wrapper belt 22 on the winding drum 3, so that the winding effect of the strip steel 4 is ensured.

Further preferably, a pressing plate is further installed on the arm holding frame, and the installation position of the pressing plate satisfies the following conditions: in the clasping state, the pressing plate is close to the winding drum 3 and is matched with the winding drum 3 to form a belt head guide channel, so that the included angle between the head of the strip steel and the coiling assisting belt 22 is smaller when the head of the strip steel enters the strip steel V-shaped inlet for the second time, and the coiling assisting is stably finished with smaller resistance. The pressing plate is arranged at one end of the arm holding frame, which is far away from the arm holding driving unit; in the above structure, after the auxiliary winding belt 22 is wound around the winding drum 3, the strip inlet and the strip outlet are formed between the auxiliary winding belt 22 and the winding drum 3, and the pressing plate can swing with the holding arm frame to the strip outlet side, and is mainly used for guiding the strip 4, so that the strip 4, especially the strip head, is attached to the winding drum 3 to be convenient to wind.

In addition, preferably, the pressing plate and the arm holding frame are rotatably connected, an adjusting bolt for driving the pressing plate to rotate relative to the arm holding frame is arranged on the arm holding frame, the pressing plate can be controlled to rotate relative to the arm holding frame through the adjusting bolt, the adjusting action is generally used for adjusting the inclination angle of the pressing plate after the arm holding frame swings, the belt head can be smoothly guided into the adjusting action through the proper inclination angle of the pressing plate, and the impact of the belt head on the belt head can be reduced.

The belt running roller is used for supporting and tensioning the wrapper belt 22 and enabling the wrapper belt 22 to circulate and run smoothly, and obviously, the belt running roller can guide the wrapper belt 22 to pass through the accommodating groove and then return to the wrapper frame 21 for circulation. As shown in fig. 1, the belt running roller system preferably comprises a plurality of supporting rollers, at least one tensioning roller and a turning roller mounted at the free end of the arm embracing mechanism, wherein each supporting roller and each tensioning roller are mounted on the winding frame 21 and located outside the accommodating groove; in one embodiment, each support roller is a convex roller with convexity, which can make the auxiliary winding belt 22 self-correct and prevent deviation, and in another embodiment, each support roller can also adopt a combination of a convex roller and a flat roller; each tensioning roller is arranged on the wrapper assisting frame 21 and can provide tension for the wrapper assisting belt 22 so as to ensure the wrapper assisting belt 22 to run stably. In an alternative embodiment, at least part of the roller seat of the supporting roller is rotatably mounted on the winding assisting frame 21, and the rotating shaft is axially parallel to the axial direction of the supporting roller, and the swinging of the supporting roller can make the winding assisting belt 22 self-correct to prevent deviation.

Further preferably, as shown in fig. 1 and fig. 4, the strip steel coiling aid device further includes a mounting frame, the coiling aid frame 21 and the components arranged on the coiling aid frame 21 can be combined into a coiling aid module 2, and the coiling aid module 2 is mounted on the mounting frame, specifically:

the mounting rack comprises a fixed rack 11 and a movable rack 12, wherein the movable rack 12 is movably mounted on the fixed rack 11, the rolling assisting module 2 is mounted on the movable rack 12, and the movable rack 12 can drive the rolling assisting module 2 to move relative to the fixed rack 11. Wherein, the movable frame 12 is movably mounted on the fixed frame 11 through a guiding mechanism, and the guiding direction of the guiding mechanism is parallel to the axis of the wrapper pressing roller 241 (i.e. parallel to the axis of the winding drum 3).

Based on the scheme, the coiling assisting modules 2 can move transversely, particularly move transversely together with the recoiling machine, and the coiling assisting modules 2 move transversely together in the process of deviation correction of the strip steel 4 by transverse movement of the recoiling machine, so that the uniformity of strip steel coiling and the quality of the strip steel can be improved.

Preferably, the movable frame 12 is fixedly connected (preferably detachably connected) with the coiler and can follow the coiler without additionally configuring a driving device for the movable frame 12, so that the follow-up response speed of the movable frame 12 is increased, and the equipment cost is reduced.

In one embodiment, one end of the movable frame 12 is connected to the fixed frame 11 through a combination of a guide shaft and a guide sleeve, the axis of the guide shaft is parallel to the axis of the wrapper pressing roller 241, and the other end of the movable frame 12 is provided with a roller, the axis of the roller is perpendicular to the axis of the guide shaft.

Further, as shown in fig. 1 and 4, the wrapper module 2 is rotatably mounted on the movable frame 12, and a swing driving unit 13 is provided on the movable frame 12, and the swing driving unit 13 is connected to the wrapper module 2. In one embodiment, the swing driving unit 13 is a swing hydraulic cylinder, a cylinder body of the swing hydraulic cylinder is hinged on the movable frame 12, and an output end of the swing hydraulic cylinder is hinged with the wrapper module 2.

Further, as shown in fig. 1 and 4, a swing bracket 121 may be provided on the movable frame 12, the swing bracket 121 being disposed near a steel-coming side of the movable frame 12 and rotatably connected to a bottom of the movable frame 12, and the winding assistant bracket 21 being mounted on the swing bracket 121. The axis of rotation of the swing support 121 is parallel to the width direction of the strip, i.e. parallel to the axial direction of the reel 3 in practical application. Adopt swing support 121 to drive and help the swing of book frame 21, on the one hand, increase helps the swing radius of book frame 21, avoid helping the swing in-process of book frame 21 to take place to interfere with other structures, on the other hand, can directly utilize current help book frame 21, need not to help book frame 21 to reform transform. Preferably, the winding assisting frame 21 is detachably mounted on the swing support 121, so that different winding assisting devices can be replaced according to actual working conditions, and meanwhile, the installation and maintenance of the winding assisting devices are facilitated.

Preferably, the fixed frame 11 includes a supporting frame 111 and a fixed platform 112, and the supporting frame 111 preferably includes a plurality of supporting columns, so that the fixed platform 112 can be supported on the base of the workshop structure, and the winding frame 21 is allowed to move between the supporting columns. According to the specification and size of the auxiliary winding frame 21, an avoidance channel can be arranged on the basis of a workshop structure. For example, a groove channel is provided to meet the requirement of the movement space of the auxiliary winding frame 21.

According to the strip steel coiling assisting device provided by the embodiment, the coiling assisting frame 21 is rotatably arranged on the mounting rack to form the swinging coiling assisting frame 21, so that the space position and the threading angle of the coiling assisting frame 21 can be conveniently adjusted, the coiling assisting frame 21 can be switched between an online position and an offline position, and the strip steel coiling assisting device can be better matched with the winding drum 3 to complete the coiling operation and the coiling operation.

In one embodiment, a strip steel conveying mechanism, such as a strip steel pinch device or a strip threading guide plate, is arranged on the top of the fixed platform 112, and when the corresponding coiling device is located in the midstream of the production line (i.e. other strip steel processing devices are located downstream of the coiling device), the strip steel 4 can be continuously conveyed through the strip steel conveying mechanism on the top of the solid platform, so that the number of devices and the occupied space are saved, and the cost is effectively saved.

The above embodiments are merely preferred embodiments of the present invention, and not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a reliable belted steel of preflex tape head helps package and puts, includes helps the book frame, help the book frame to have the C type that can accept the reel and accomodate the groove, help being equipped with belt operation roller system and coiling on the book frame help a roll belt on the belt operation roller system, its characterized in that: the roll-up aiding frame is further provided with an auxiliary roll-up aiding mechanism, the auxiliary roll-up aiding mechanism comprises a roll-up aiding roller seat, a plurality of roll-up aiding compression rollers arranged on the roll-up aiding roller seat and a compression roller driving unit used for driving the roll-up aiding roller seat to move so as to change the distance between the roll-up compression rollers and the winding drum, and the roll-up aiding roller seat is hinged on the accommodating groove body and axially parallel to the roll-up compression roller in the axial direction of the hinge shaft.

2. The strip steel coiling aid device capable of reliably pre-bending a strip head as claimed in claim 1, wherein: and the compression roller driving unit is connected to the tail part of the wrapper roller seat along the running direction of the strip steel.

3. The strip steel coiling aid device capable of reliably pre-bending a strip head as claimed in claim 2, wherein: the compression roller driving unit adopts an air cylinder, a hydraulic cylinder or an electric push rod.

4. The strip steel wrapper capable of reliably pre-bending a strip head as claimed in claim 1, wherein: and the auxiliary winding press rollers on the auxiliary winding roller seat are sequentially arranged at intervals along the circumferential direction of the C-shaped accommodating groove to form a roller row, and the guide surface of the roller row is an arc-shaped surface.

5. The strip steel wrapper capable of reliably pre-bending a strip head as claimed in claim 1, wherein: the auxiliary winding assisting mechanisms are provided with a plurality of groups, and the auxiliary winding assisting mechanisms are sequentially arranged along the circumferential direction of the C shape of the accommodating groove.

6. The strip steel wrapper capable of reliably pre-bending a strip head as claimed in claim 1, wherein: arm holding mechanisms used for being matched with the winding drum for winding are respectively arranged at two ends of the notch of the accommodating groove.

7. The strip steel coiling aid device capable of reliably pre-bending a strip head as claimed in claim 6, wherein: the belt running roller system comprises a plurality of supporting rollers, at least one tensioning roller and a steering roller arranged at the free end of the arm-holding mechanism; the arm embracing mechanism comprises an arm embracing driving unit and an arm embracing frame which is rotatably arranged on the roll assisting frame, and the arm embracing frame is connected with the arm embracing driving unit so as to drive the steering roller to swing to an embracing state close to the winding drum and an opening state far away from the winding drum.

8. The strip steel coiling assisting device capable of reliably pre-bending a strip head as claimed in claim 7, wherein a pressure plate is further arranged on the arm holding frame, and the installation position of the pressure plate satisfies the following conditions: in the clasping state, the pressure plate is close to the winding drum and is matched with the winding drum to form a belt head guide channel.

9. The strip steel coiling aid device capable of reliably pre-bending a strip head as claimed in claim 6, wherein: the belt running roller system comprises a plurality of supporting rollers, at least one tensioning roller and a turning roller arranged at the free end of the arm embracing mechanism, wherein each supporting roller and each tensioning roller are arranged on the auxiliary winding frame and are positioned outside the accommodating groove.