CN218153377U

CN218153377U - Computer rotating support

Info

Publication number: CN218153377U
Application number: CN202221851266.3U
Authority: CN
Inventors: 孙平军
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-07-18
Filing date: 2022-07-18
Publication date: 2022-12-27
Anticipated expiration: 2032-07-18

Abstract

The utility model discloses a computer rotating bracket, including base and bracket component, the bracket component includes rotating part, the base includes chassis and mounting that link to each other, the base has the axial region, rotating part rotating sleeve is established on the axial region, still include the locking structure, the locking structure includes eccentric mechanism, locking piece, elastic component and locates the cyclic annular locking surface on the rotating part, be equipped with the holding tank on the axial region and communicate the outer wall of axial region and the spout of holding tank, one end of locking piece is located the holding tank, the other end of locking piece is equipped with the contact of supporting that cooperates with the cyclic annular locking surface; the elastic piece contacts the locking piece and the base to drive the locking piece to retract; the eccentric mechanism is rotatably arranged on the fixing piece, part of the area of the eccentric mechanism is exposed out of the upper surface of the fixing piece, the eccentric mechanism contacts the locking piece, and the eccentric mechanism is used for driving the abutting head to abut against the annular locking surface. This computer runing rest has rotation angle locking function, can make the locking that rotates the piece and realize relative position with the base, has strengthened user's use and has experienced.

Description

Computer rotating support

Technical Field

The utility model relates to a computer support technical field especially relates to computer runing rest.

Background

The computer rotating bracket is suitable for a notebook computer, a tablet computer or other electronic equipment, the existing computer rotating bracket generally comprises a base and a bracket component which are connected, and the base and the bracket component are generally in rotatable connection in order to facilitate the adjustment of the direction of the electronic equipment supported by the computer rotating bracket. However, if the user accidentally hits the stand assembly or the electronic device supported by the stand assembly slightly, the stand assembly may be accidentally rotated to cause unintended rotation of the electronic device, which may degrade the user experience.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem that will solve is: the computer rotating bracket can prevent the bracket component from rotating accidentally.

In order to solve the technical problem, the utility model discloses a technical scheme be: the computer rotating support comprises a base and a support component, wherein the support component comprises a rotating piece, the base comprises a chassis and a fixing piece which are connected, the base is provided with a shaft part, the rotating piece is sleeved on the shaft part in a rotating manner, the computer rotating support further comprises a locking structure, the locking structure comprises an eccentric mechanism, a locking piece, an elastic piece and an annular locking surface arranged on the rotating piece, an accommodating groove and a sliding groove communicated with the outer wall of the shaft part and the accommodating groove are formed in the shaft part, one end of the locking piece is positioned in the accommodating groove, and the other end of the locking piece is provided with a contact matched with the annular locking surface; the elastic piece contacts the locking piece and the base to drive the locking piece to retract; the eccentric mechanism is rotatably arranged on the fixing piece, part of the area of the eccentric mechanism is exposed out of the upper surface of the fixing piece, the eccentric mechanism contacts the locking piece, and the eccentric mechanism is used for driving the abutting head to abut against the annular locking surface.

Further, the eccentric mechanism includes a round block and a rotating shaft, the round block is located in the accommodating groove, the locking piece has an abutting surface abutting against the peripheral wall of the round block, the rotating shaft is rotatably arranged on the fixing piece, one end of the rotating shaft is exposed out of the upper surface of the fixing piece, and the other end of the rotating shaft extends into the accommodating groove and is eccentrically connected with the round block.

Furthermore, one end of the rotating shaft, which is far away from the round block, is connected with a handle.

The limiting device further comprises a limiting column and an arc-shaped limiting groove which are matched, wherein the limiting column is arranged on the round block, and the arc-shaped limiting groove is arranged on the fixing piece; or, the limiting column is arranged on the fixing piece, and the arc-shaped limiting groove is arranged on the round block.

Furthermore, the rotating shaft is provided with a non-circular limiting protrusion, and the round block is provided with a non-circular limiting groove matched with the non-circular limiting protrusion.

Further, still be equipped with the elasticity mechanism of contradicting on the base, it has a plurality of tooth's sockets that are the round setting to rotate to have on the piece, the subregion of elasticity mechanism of contradicting stretches into in the tooth's socket.

Furthermore, the elastic abutting mechanism is a ball plunger or a spring sheet.

Furthermore, the abutting head is provided with a non-slip pad, and the abutting head abuts against the annular locking surface through the non-slip pad.

Furthermore, the upper surface of the fixing piece is provided with a prompt mark.

Further, the cover is equipped with wear-resisting position circle on the axial region, the periphery wall of wear-resisting position circle with rotate the piece contact.

The beneficial effects of the utility model reside in that: this computer runing rest has rotation angle locking function, and after the user rotated the bracket component to suitable position, the usable eccentric mechanism of user ordered about the conflict head of locking piece and the cyclic annular locking surface of rotating the piece conflict and form and keep to make the locking that rotates piece and base realization relative position, and then prevent effectively that the bracket component from taking place unexpected rotation for the base, strengthened user's use greatly and experienced. The computer rotating bracket also has the advantages of few parts, simple structure, convenience in processing and assembling, low manufacturing cost and the like.

Drawings

Fig. 1 is a schematic structural view of a computer rotating stand according to a first embodiment of the present invention;

FIG. 2 is a sectional view of a partial region of a computer rotation stand according to a first embodiment of the present invention;

fig. 3 is a schematic view of an internal structure of a base in a computer rotation stand according to a first embodiment of the present invention;

fig. 4 is a schematic view of an internal structure of a base in a computer rotation stand according to a first embodiment of the present invention (after a part of the structure is hidden on the basis of fig. 3);

fig. 5 is a schematic structural view of a locking member in a computer rotating stand according to an embodiment of the present invention.

Description of reference numerals:

1. a base; 11. a chassis; 12. a fixing member; 13. a shaft portion; 131. accommodating grooves; 132. a chute; 133. an arc-shaped limiting groove;

2. a bracket assembly; 21. a rotating member; 211. an annular locking surface; 212. a tooth socket; 22. a connecting member; 23. a support member; 231. a support surface; 232. a support block;

3. an eccentric mechanism; 31. a rotating shaft; 311. a non-circular limiting protrusion; 32. a round block; 321. a limiting column; 322. a non-circular spacing groove; 33. a handle;

4. a locking member; 41. abutting against the contact; 411. a slot; 42. a limiting part; 421. a stopper; 422. a receiving groove; 43. a projection; 44. limiting a guide hole; 45. a limiting frame;

5. an elastic member;

6. a limiting guide block;

7. a non-slip mat;

8. an elastic abutting mechanism;

9. prompting the identification;

10. a wear-resistant positioning ring;

20. a first thrust bearing; 30. a second thrust bearing.

Detailed Description

In order to explain the technical content, the objects and the effects of the present invention in detail, the following description is made with reference to the accompanying drawings in combination with the embodiments.

Referring to fig. 1 to 5, a computer rotating bracket includes a base 1 and a bracket assembly 2, the bracket assembly 2 includes a rotating member 21, the base 1 includes a chassis 11 and a fixing member 12 connected to each other, the base 1 has a shaft portion 13, the rotating member 21 is rotatably sleeved on the shaft portion 13, and further includes a locking structure, the locking structure includes an eccentric mechanism 3, a locking member 4, an elastic member 5 and an annular locking surface 211 disposed on the rotating member 21, the shaft portion 13 is provided with an accommodating groove 131 and a sliding groove 132 communicating an outer wall of the shaft portion 13 with the accommodating groove 131, one end of the locking member 4 is located in the accommodating groove 131, and the other end of the locking member 4 is provided with a contact head 41 engaged with the annular locking surface 211; the elastic piece 5 contacts the locking piece 4 and the base 1 to drive the locking piece 4 to retract; the eccentric mechanism 3 is rotatably disposed on the fixing member 12, a partial region of the eccentric mechanism 3 is exposed out of the upper surface of the fixing member 12, the eccentric mechanism 3 contacts the locking member 4, and the eccentric mechanism 3 is used for driving the abutting contact 41 to abut against the annular locking surface 211.

From the above description, the beneficial effects of the utility model reside in that: this computer runing rest has rotation angle locking function, and after the user rotated bracket component 2 to suitable position, the usable eccentric mechanism 3 of user drove the conflict head 41 of locking piece 4 and contradict and form the maintenance with the cyclic annular locking surface 211 that rotates piece 21 to make and rotate piece 21 and base 1 and realize the locking of relative position, and then prevent effectively that bracket component 2 from taking place unexpected the rotation for base 1, strengthened user's use experience greatly. The computer rotating bracket also has the advantages of few parts, simple structure, convenience in processing and assembling, low manufacturing cost and the like.

Further, the eccentric mechanism 3 includes a circular block 32 and a rotating shaft 31, the circular block 32 is located in the accommodating groove 131, the locking member 4 has an abutting surface abutting against the circumferential wall of the circular block 32, the rotating shaft 31 is rotatably disposed on the fixing member 12, one end of the rotating shaft 31 is exposed out of the upper surface of the fixing member 12, and the other end of the rotating shaft 31 extends into the accommodating groove 131 and is eccentrically connected with the circular block 32.

As can be seen from the above description, the eccentric mechanism 3 has simple structure, easy processing and manufacture and low production cost.

Further, a handle 33 is connected to one end of the rotating shaft 31 away from the round block 32.

As can be seen from the above description, the presence of the handle 33 facilitates the user to rotate the eccentric mechanism 3, which is beneficial to further enhance the user experience.

Further, the device also comprises a limit post 321 and an arc-shaped limit groove 133 which are matched, wherein the limit post 321 is arranged on the round block 32, and the arc-shaped limit groove 133 is arranged on the fixing piece 12; alternatively, the limiting column 321 is disposed on the fixing element 12, and the arc-shaped limiting groove 133 is disposed on the round block 32.

As can be seen from the above description, the engagement between the limiting post 321 and the arc-shaped limiting groove 133 can limit the range of the rotation angle of the eccentric mechanism 3 relative to the base 1, so as to avoid the situation that the user cannot lock or unlock the locking member 4 due to the excessive rotation of the eccentric mechanism 3.

Furthermore, a non-circular limiting protrusion 311 is arranged on the rotating shaft 31, and a non-circular limiting groove 322 matched with the non-circular limiting protrusion 311 is arranged on the round block 32.

From the above description, it can be known that the fitting of the non-circular limiting protrusion 311 and the non-circular limiting groove 322 can realize good locking between the rotating shaft 31 and the round block 32, so as to prevent the round block 32 from rotating relative to the rotating shaft 31, and to ensure the working stability of the locking structure.

Further, still be equipped with elasticity conflict mechanism 8 on the base 1, rotate and have a plurality of tooth's socket 212 that are the round setting on the piece 21, the regional partial region of elasticity conflict mechanism 8 stretches into in the tooth's socket 212.

As can be seen from the above description, in the rotation process of the rotating member 21, the elastic interference mechanism 8 makes a sound when it touches different tooth slots 212, which is beneficial to enhancing the operation hand feeling of the computer rotation bracket; moreover, when the locking structure is unlocked accidentally, the elastic interference mechanism 8 can limit the rotation of the rotation member 21 relative to the base 1 to a certain extent.

Further, the elastic abutting mechanism 8 is a ball plunger or a spring.

As can be seen from the above description, the specific configuration of the elastic abutting mechanism 8 is various and can be selected as required.

Further, the abutting contact 41 is provided with a non-slip pad 7, and the abutting contact 41 abuts against the annular locking surface 211 through the non-slip pad 7.

As can be seen from the above description, the presence of the non-slip mat 7 can increase the friction between the rotating piece 21 and the locking piece 4 when the locking structure is locked, so that the rotating piece 21 and the locking piece 4 can be locked more stably, which is beneficial to ensuring the locking effect.

Further, the upper surface of the fixing part 12 is provided with a prompt mark 9.

As described above, the prompt mark 9 is used to prompt the user of the real-time status of the locking structure, so that the user can quickly know whether the locking structure is in the locked state or the unlocked state.

Further, the shaft part 13 is sleeved with a wear-resistant locating ring 10, and the peripheral wall of the wear-resistant locating ring 10 is in contact with the rotating part 21.

As can be seen from the above description, the wear-resistant retainer ring 10 can facilitate the positioning and installation of the rotating member 21, and at the same time, the wear-resistant retainer ring 10 has a long service life because it is made of a wear-resistant material.

Example one

Referring to fig. 1 to 5, a first embodiment of the present invention is: the computer rotating bracket comprises a base 1 and a bracket assembly 2, wherein the bracket assembly 2 comprises a rotating piece 21, a connecting piece 22 and a supporting piece 23, one end of the connecting piece 22 is rotatably connected with the rotating piece 21, the other end of the connecting piece 22 is rotatably connected with the supporting piece 23, the supporting piece 23 is provided with a supporting surface 231, a supporting block 232 is arranged on the supporting surface 231, the supporting surface 231 is used for supporting electronic equipment placed on the supporting surface 231, the electronic equipment comprises but is not limited to a notebook computer, a tablet computer and the like, and the supporting block 232 is used for preventing the electronic equipment from falling off the supporting surface 231; in this embodiment, the connecting member 22 is a connecting rod, and in other embodiments, the connecting member 22 may be a telescopic rod or the like.

Referring to fig. 1 to 3, the base 1 includes a chassis 11 and a fixing element 12 connected to each other, the base 1 has a shaft portion 13, the rotating element 21 is rotatably sleeved on the shaft portion 13, and further includes a locking structure, the locking structure includes an eccentric mechanism 3, a locking element 4, an elastic element 5, and an annular locking surface 211 disposed on the rotating element 21, the locking element 4 is disposed in a hollow region of the annular locking surface 211, the shaft portion 13 is provided with an accommodating groove 131 and a sliding groove 132 for communicating an outer wall of the shaft portion 13 with the accommodating groove 131, one end of the locking element 4 is disposed in the accommodating groove 131, and the other end of the locking element 4 is provided with a contact head 41 engaged with the annular locking surface 211; the elastic piece 5 contacts the locking piece 4 and the base 1 to drive the locking piece 4 to retract; the eccentric mechanism 3 is rotatably disposed on the fixing member 12, a partial region of the eccentric mechanism 3 is exposed out of the upper surface of the fixing member 12, the eccentric mechanism 3 contacts the locking member 4, and the eccentric mechanism 3 is used for driving the abutting contact 41 to abut against the annular locking surface 211. The elastic piece 5 can be a spring, an elastic sheet, an elastic pad and the like.

As will be readily understood, the sliding groove 132 is communicated with the receiving groove 131 to form a sliding groove in which the locking member 4 is slidable, and the bottom plate 11 closes the sliding groove to limit the locking member 4 so as to prevent the locking member 4 from being disengaged from the sliding groove. The locking piece 4 is a sliding block, in this embodiment, the sliding block is substantially in a shape of a Chinese character 'ao', in detail, the locking piece 4 includes a limiting portion 42 and a protruding portion 43 connected to each other, the limiting portion 42 is located in the accommodating groove 131, the protruding portion 43 is located in the sliding groove 132, and one end of the protruding portion 43 away from the limiting portion 42 is provided with the abutting contact 41; the quantity of elastic component 5 is two, bulge 43 is located two between the elastic component 5, be equipped with dog 421 in the spacing portion 42, elastic component 5 contradicts dog 421 with axial region 13, preferentially, spacing portion 42 is kept away from chassis 11 one side is equipped with and is used for accomodating the groove 422 is accomodate to the subregion of elastic component 5.

Referring to fig. 3 and 4, in order to ensure the smoothness of the sliding of the locking member 4, optionally, a limiting guide block 6 is disposed on the shaft portion 13, a limiting guide hole 44 matched with the limiting guide block 6 is disposed on the locking member 4, and a long axis direction of the limiting guide hole 44 is consistent with a sliding direction of the locking member 4. Optionally, the cross section of the limiting guide block 6 is convex. Optionally, the limiting guide block 6 is connected with the shaft 13 by a snap or a screw.

Referring to fig. 2 and fig. 5, as a preferred embodiment, a non-slip pad 7 is disposed on the abutting contact 41, and the abutting contact 41 abuts against the annular locking surface 211 through the non-slip pad 7. Optionally, the abutting head 41 is provided with a slot 411 for mounting the non-slip mat 7. The material of the non-slip mat 7 can be rubber and the like. Further, the side of the anti-slip pad 7 close to the annular locking surface 211 may be provided with anti-slip lines, which include, but are not limited to, stripe lines, diamond lines, etc.

As shown in fig. 2, in this embodiment, the shaft portion 13 is disposed on the fixing member 12, the shaft portion 13 and the fixing member 12 may be an integral structure formed by integral processing, or may be a split structure connected by a screw, a buckle or other structures, in other embodiments, the shaft portion 13 may be disposed on the chassis 11, or the shaft portion 13 includes a first portion disposed on the fixing member 12 and a second portion disposed on the chassis 11, in which case, the first portion and the second portion are coaxial and opposite to each other.

Referring to fig. 2 to 4, the eccentric mechanism 3 includes a circular block 32 and a rotating shaft 31, the circular block 32 is located in the accommodating groove 131, the locking member 4 has an abutting surface abutting against a peripheral wall of the circular block 32, the rotating shaft 31 is rotatably disposed on the fixing member 12, one end of the rotating shaft 31 is exposed out of an upper surface of the fixing member 12, and the other end of the rotating shaft 31 extends into the accommodating groove 131 and is eccentrically connected to the circular block 32. Optionally, the locking member 4 has a limiting frame 45, the round block 32 is located in the limiting frame 45, and the abutting surface is a partial area of an inner wall surface of the limiting frame 45.

As shown in fig. 1 and 2, in order to facilitate the operation of the user, a handle 33 is connected to an end of the rotating shaft 31 away from the round block 32, the handle 33 and the rotating shaft 31 may be an integrated structure formed by integral processing, or may be a split structure connected together, and at this time, the connection manner of the handle 33 and the rotating shaft 31 includes, but is not limited to, screw connection, snap connection, adhesive connection, threaded connection, and the like.

Referring to fig. 2 and 4, as a preferred embodiment, the computer rotation bracket further includes a limiting post 321 and an arc-shaped limiting groove 133, which are matched with each other, the limiting post 321 is disposed on the round block 32, and the arc-shaped limiting groove 133 is disposed on the fixing member 12; alternatively, the limiting column 321 is disposed on the fixing member 12, and the arc-shaped limiting groove 133 is disposed on the round block 32. Optionally, the arc-shaped limiting groove 133 is a 1/4 arc-shaped groove. In some embodiments, the two end regions of the arc-shaped limiting groove 133 are provided with pits, and the limiting column 321 is a ball plunger, and the ball plunger is matched with the pits, so that the risk of accidental rotation of the round block 32 can be reduced.

As shown in fig. 2, the rotating shaft 31 is connected to the round block 32 by screws, in order to prevent the round block 32 from rotating relative to the rotating shaft 31, a non-circular limiting protrusion 311 is provided on the rotating shaft 31, the non-circular limiting protrusion 311 is located at an end of the rotating shaft 31 far away from one end of the handle 33, and a non-circular limiting groove 322 matched with the non-circular limiting protrusion 311 is provided on the round block 32. The non-circular limiting protrusion 311 includes, but is not limited to, a triangular block, a rectangular block, an oval block 32, etc. It is understood that the non-circular limiting protrusion 311 is disposed on the round block 32, and the non-circular limiting groove 322 is disposed on the rotating shaft 31.

Referring to fig. 2 to 4, in order to enhance the operation feeling of the rotating member 21 during rotation and further reduce the risk of the rotating member 21 rotating unexpectedly, optionally, the base 1 is further provided with an elastic abutting mechanism 8, the rotating member 21 is provided with a plurality of tooth slots 212 arranged in a circle, and a partial area of the elastic abutting mechanism 8 extends into the tooth slots 212. In this embodiment, the elastic abutting mechanism 8 is a spring, and the spring may be made of metal or plastic. In other embodiments, the elastic interference mechanism 8 may also be a ball plunger or other structures.

As shown in fig. 1, a prompt mark 9 is disposed on an upper surface of the fixing member 12, in this embodiment, the prompt mark 9 includes a locking mark, an unlocking mark, and a turning mark, and the turning mark is located between the locking mark and the unlocking mark.

As shown in fig. 2, for the convenience of positioning and installing the rotating part 21 and the fixing part 12, the shaft part 13 is sleeved with a wear-resistant locating ring 10, the peripheral wall of the wear-resistant locating ring 10 contacts with the rotating part 21, the wear-resistant locating ring 10 is made of a wear-resistant material, and the wear-resistant material includes but is not limited to teflon.

In detail, the edge of the fixed part 12 has a skirt portion protruding outwards, the skirt portion with be equipped with first footstep bearing 20 between the rotation piece 21, first footstep bearing 20 contacts respectively the skirt portion with rotate the piece 21, the chassis 11 with be equipped with second footstep bearing 30 between the rotation piece 21, second footstep bearing 30 contacts respectively rotate the piece 21 with the chassis 11, first footstep bearing 20 and second footstep bearing 30's setting can let and rotate a piece 21 and rotate more smoothly. In order to facilitate the positioning and installation of the first thrust bearing 20 and the second thrust bearing 30, the rotating member 21 is provided with a first groove and a second groove, a partial area of the first thrust bearing 20 is located in the first groove, and a partial area of the second thrust bearing 30 is located in the second groove.

To sum up, the utility model provides a computer runing rest has rotation angle locking function, and after the user rotated the bracket component suitable position, the usable eccentric mechanism of user ordered about the conflict head of locking piece and the cyclic annular locking surface of rotating the piece contradicts and forms and keeps to make the locking that rotates the piece and realize relative position with the base, and then prevent effectively that the bracket component from taking place unexpected the rotation for the base, strengthened user's use greatly and experienced. The computer rotating bracket also has the advantages of few parts, simple structure, convenience in processing and assembling, low manufacturing cost and the like.

The above mentioned is only the embodiment of the present invention, and not the limitation of the patent scope of the present invention, all the equivalent transformations made by the contents of the specification and the drawings, or the direct or indirect application in the related technical field, are included in the patent protection scope of the present invention.

Claims

1. Computer runing rest, including base and bracket component, the bracket component is including rotating the piece, the base is including the chassis and the mounting that link to each other, the base has the axial region, it establishes to rotate the rotation cover in the axial region, its characterized in that: the locking structure comprises an eccentric mechanism, a locking piece, an elastic piece and an annular locking surface arranged on the rotating piece, wherein the shaft part is provided with an accommodating groove and a sliding groove for communicating the outer wall of the shaft part with the accommodating groove; the elastic piece contacts the locking piece and the base to drive the locking piece to retract; the eccentric mechanism is rotatably arranged on the fixing piece, part of the area of the eccentric mechanism is exposed out of the upper surface of the fixing piece, the eccentric mechanism contacts the locking piece, and the eccentric mechanism is used for driving the abutting head to abut against the annular locking surface.

2. The rotating rack of computer as claimed in claim 1, wherein: the eccentric mechanism comprises a round block and a rotating shaft, the round block is located in the accommodating groove, the locking piece is provided with an abutting surface abutting against the peripheral wall of the round block, the rotating shaft is rotatably arranged on the fixing piece, one end of the rotating shaft is exposed out of the upper surface of the fixing piece, and the other end of the rotating shaft extends into the accommodating groove and is eccentrically connected with the round block.

3. The computer rotating stand of claim 2, wherein: and one end of the rotating shaft, which is far away from the round block, is connected with a handle.

4. The computer rotation stand of claim 2, wherein: the limiting device also comprises a limiting post and an arc-shaped limiting groove which are matched, wherein the limiting post is arranged on the round block, and the arc-shaped limiting groove is arranged on the fixing piece; or, the limiting column is arranged on the fixing piece, and the arc-shaped limiting groove is arranged on the round block.

5. The computer rotation stand of claim 2, wherein: the rotating shaft is provided with a non-circular limiting protrusion, and the round block is provided with a non-circular limiting groove matched with the non-circular limiting protrusion.

6. The computer rotation stand of claim 1, wherein: the base is further provided with an elastic interference mechanism, the rotating piece is provided with a plurality of tooth sockets arranged in a circle, and partial area of the elastic interference mechanism extends into the tooth sockets.

7. The computer rotation stand of claim 6, wherein: the elastic abutting mechanism is a ball plunger or a spring piece.

8. The rotating rack of computer as claimed in claim 1, wherein: the anti-slip head is provided with an anti-slip pad, and the anti-slip head abuts against the annular locking surface through the anti-slip pad.

9. The rotating rack of computer as claimed in claim 1, wherein: the upper surface of the fixing piece is provided with a prompt mark.

10. The rotating rack of computer as claimed in claim 1, wherein: the cover is equipped with wear-resisting position circle on the axial region, the periphery wall of wear-resisting position circle with rotate the piece contact.