Omni-directional angle body position supporting frame for operative body position

Abstract

The utility model relates to the technical field of medical instruments, and provides a surgical position all-dimensional angle position supporting frame which comprises a fixing base, a supporting rod, a first angle adjusting rod, a second angle adjusting rod, a ball cup and a baffle. The supporting rod is arranged on the fixed seat; one end of the first angle adjusting rod is arranged on the supporting rod, and the other end is close to or away from the operating bed after rotation; one end of the second angle adjusting rod is arranged on the first angle adjusting rod, and the other end is close to or away from the operating bed after rotation; the ball cup is arranged on the second angle adjusting rod; a ball head is arranged on the baffle and rotationally arranged in the ball head seat, and the baffle is used for making contact with the body of a patient. By means of the technical scheme, the problems that in the prior art, when a body position supporting frame is placed on a large-weight person group, the angle is limited, the baffle cannot rotate to the effective position, and the requirement for surgical body position placing cannot be met are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, and in particular to an all-round angle body support frame for surgical body positions. Background Art

[0002] The body support frame is used to stabilize and position the patient's body during surgery, ensuring accurate exposure of the surgical area while reducing stress and discomfort to the patient. The design and use of the body support frame not only involves the precision of mechanical engineering, but also needs to consider the requirements of human physiology and medical practice. It plays an indispensable role in modern medical surgery and can contribute to the success of the surgery and the recovery of the patient. With the increase in the number of people with large body weight undergoing surgery, the existing body support frames are limited by the angle when positioning the large body weight people, and the baffle cannot be rotated to an effective position, which cannot meet the needs of surgical positioning. The body position of the large body weight people cannot be effectively fixed, which will affect the progress of the operation, and cannot prevent the patient from falling out of bed, and cannot better play a supporting role. Utility Model Content

[0003] The utility model provides an all-round angle body support frame for surgical positions, which solves the problem in the related art that the body support frame is limited by angle when placed on a heavy person, the baffle cannot be rotated to an effective position, and the need for surgical position placement cannot be met.

[0004] The technical solution of the utility model is as follows: a surgical posture all-round angle posture support frame, the key is: including:

[0005] A fixing seat, the fixing seat is used to be locked on the operating table;

[0006] A support rod, wherein the support rod is arranged on the fixing seat;

[0007] a first angle adjustment rod, one end of which is arranged on the support rod and the other end of which is moved closer to or farther from the operating table after rotation;

[0008] a second angle adjustment rod, one end of which is arranged on the first angle adjustment rod and the other end of which is moved closer to or farther from the operating table after rotation;

[0009] A ball head seat, the ball head seat is arranged on the second angle adjustment rod;

[0010] A baffle is provided with a ball head, the ball head is rotatably arranged in the ball head seat, and the baffle is used to contact the patient's body.

[0011] It also includes a first locking member, and the first angle adjustment rod includes:

[0012] A first transverse rod, one end of which is rotatably disposed on the support rod and is locked with the support rod by means of the first locking member;

[0013] A first longitudinal rod is disposed between the first transverse rod and the second angle adjustment rod.

[0014] It also includes a first rotating sleeve, which is arranged at one end of the first transverse rod close to the support rod, the first rotating sleeve is sleeved on the periphery of the support rod and is rotatably connected thereto, the upper end of the support rod has a first supporting surface, the lower end of the first locking piece passes through the first rotating sleeve and is threadedly connected to the support rod, and the first rotating sleeve is clamped between the upper end of the first locking piece and the first supporting surface.

[0015] It also includes a second locking member, and the second angle adjustment rod includes:

[0016] a second transverse rod, one end of which is rotatably disposed on the first longitudinal rod and is locked with the first longitudinal rod by means of the second locking member;

[0017] A second longitudinal rod is disposed between the second transverse rod and the ball head seat.

[0018] It also includes a second rotating sleeve, which is arranged at one end of the second transverse rod close to the first longitudinal rod, the second rotating sleeve is sleeved on the outer periphery of the first longitudinal rod and is rotatably connected thereto, the upper end of the first longitudinal rod has a second supporting surface, the lower end of the second locking piece passes through the second rotating sleeve and is threadedly connected to the first longitudinal rod, and the second rotating sleeve is clamped between the upper end of the second locking piece and the second supporting surface.

[0019] Also includes,

[0020] A positioning sleeve, wherein the positioning sleeve is arranged on the second angle adjustment rod, the axis of the positioning sleeve is arranged horizontally, the ball head seat is arranged coaxially with the positioning sleeve, and the ball head seat is arranged on the second angle adjustment rod by means of the positioning sleeve;

[0021] A third locking piece is threadedly connected to the positioning sleeve, the ball head is locked in the ball head seat by means of the third locking piece, and the other end of the third locking piece is located at the periphery of the positioning sleeve.

[0022] The ball head comprises:

[0023] A sphere, the sphere being rotatably disposed in the ball head seat, and the inner diameter of the end of the ball head seat away from the positioning sleeve is smaller than the diameter of the sphere;

[0024] The rod body is arranged between the spherical body and the baffle, and a notch is provided on the end surface of the ball head seat away from the positioning sleeve. The rod body is engaged with or separated from the notch after rotation.

[0025] It also includes a locking rod, the fixing seat is mounted on the operating bed, a mounting hole is opened on the fixing seat, the mounting hole is located outside the operating bed, a threaded hole is arranged at a position on the operating bed corresponding to the mounting hole, one end of the locking rod passes through the mounting hole and is threadedly connected with the threaded hole, and the other end of the locking rod is located outside the fixing seat.

[0026] It also includes an operating handle, which is arranged on the locking rod, and the operating handle is arranged perpendicular to the locking rod.

[0027] The baffle has a fixing surface and a supporting surface. The ball head is arranged on the fixing surface. The supporting surface is an arc-shaped surface with a middle portion concave toward the ball head.

[0028] The working principle and beneficial effects of the utility model are as follows: the fixed seat is used to lock on the operating bed, the support rod is arranged on the fixed seat, one end of the first angle adjustment rod is arranged on the support rod, and the other end is close to or away from the operating bed after rotation, one end of the second angle adjustment rod is arranged on the first angle adjustment rod, and the other end is close to or away from the operating bed after rotation, the ball head seat is arranged on the second angle adjustment rod, and a ball head is arranged on the baffle, and the ball head is rotatably arranged in the ball head seat, and the baffle is used to contact the patient's body. When in use, the support frame is locked on the operating bed through the fixed seat, and the first angle adjustment rod and the second angle adjustment rod can both rotate horizontally, thereby changing the distance between the baffle and the operating bed, which has higher flexibility, can increase the movable angle of the baffle, ensure that the baffle is in surface contact with the patient's body, the contact area is large enough, the stability of the support fixation is better, and the patient is more comfortable. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The preferred implementation modes will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present utility model.

[0030] Figure 1 It is the front view of the utility model.

[0031] Figure 2 It is a left view of the connection between the middle baffle and the ball head seat of the utility model.

[0032] In the figure: 1, fixed seat, 2, support rod, 3, first angle adjustment rod, 3-1, first transverse rod, 3-2, first longitudinal rod, 4, second angle adjustment rod, 4-1, second transverse rod, 4-2, second longitudinal rod, 5, ball head seat, 6, baffle, 7, ball head, 7-1, sphere, 7-2, rod body, 8, first locking piece, 9, first rotating sleeve, 10, first supporting surface, 11, second locking piece, 12, second rotating sleeve, 13, second supporting surface, 14, positioning sleeve, 15, third locking piece, 16, notch, 17, locking rod, 18, operating handle, 19, fixed surface, 20, supporting surface. DETAILED DESCRIPTION

[0033] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the specific implementation methods of the utility model will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0034] In order to simplify the drawings, only the parts related to the utility model are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically shown, or only one of them is marked. In this article, "one" not only means "only one", but also means "more than one", and "several" includes "two" and "more than two".

[0035] In this article, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0036] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0037] Example, see Figure 1~Figure 2, which is an embodiment of the utility model, proposes an all-round angle support frame for surgical posture, including a fixed seat 1, a support rod 2, a first angle adjustment rod 3, a second angle adjustment rod 4, a ball head seat 5, and a baffle 6. The fixed seat 1 is used to be locked on the operating bed; the support rod 2 is arranged on the fixed seat 1; one end of the first angle adjustment rod 3 is arranged on the support rod 2, and the other end is close to or away from the operating bed after rotation; one end of the second angle adjustment rod 4 is arranged on the first angle adjustment rod 3, and the other end is close to or away from the operating bed after rotation; the ball head seat 5 is arranged on the second angle adjustment rod 4; a ball head 7 is arranged on the baffle 6, and the ball head 7 is rotatably arranged in the ball head seat 5, and the baffle 6 is used to contact the patient's body.

[0038] Furthermore, if Figure 1 As shown, the first angle adjustment rod 3 also includes a first locking member 8. The first angle adjustment rod 3 includes a first transverse rod 3-1 and a first longitudinal rod 3-2. One end of the first transverse rod 3-1 is rotatably arranged on the support rod 2 and is locked with the support rod 2 by means of the first locking member 8. The first longitudinal rod 3-2 is arranged between the first transverse rod 3-1 and the second angle adjustment rod 4. The right end of the first transverse rod 3-1 can rotate around the support rod 2 in a horizontal plane, so that the left end of the first transverse rod 3-1 drives the components located thereon to approach or move away from the operating table, so that the baffle 6 approaches or moves away from the patient's body. After adjustment, the first transverse rod 3-1 can be locked on the support rod 2 by means of the first locking member 8. The structure is simple, the adjustment is convenient and quick, and time and labor saving are saved.

[0039] Furthermore, if Figure 1 As shown, it also includes a first rotating sleeve 9, which is arranged at one end of the first transverse rod 3-1 close to the support rod 2, and the first rotating sleeve 9 is sleeved on the outer periphery of the support rod 2 and is rotatably connected thereto. The upper end of the support rod 2 has a first supporting surface 10, and the lower end of the first locking member 8 passes through the first rotating sleeve 9 and is threadedly connected to the support rod 2, and the first rotating sleeve 9 is clamped between the upper end of the first locking member 8 and the first supporting surface 10. The right end of the first transverse rod 3-1 is sleeved on the support rod 2 through the first rotating sleeve 9, and the outer diameter of the part of the support rod 2 located above the first supporting surface 10 is smaller than the diameter of the lower part, so that the first rotating sleeve 9 can be placed on the first supporting surface 10 after being sleeved from top to bottom to the outer periphery of the support rod 2, and then the lower end of the first locking member 8 passes through the first rotating sleeve 9 and is threadedly connected to the support rod 2, and after adjusting the position of the first transverse rod 3-1, the first locking member 8 is screwed down to clamp the first rotating sleeve 9 between the upper end of the first locking member 8 and the first supporting surface 10. The structure is simple, the connection is firm and reliable, and the assembly and disassembly are convenient and quick, saving time and effort.

[0040] Furthermore, if Figure 1As shown, the second angle adjustment rod 4 also includes a second locking member 11. The second angle adjustment rod 4 includes a second transverse rod 4-1 and a second longitudinal rod 4-2. One end of the second transverse rod 4-1 is rotatably arranged on the first longitudinal rod 3-2 and is locked with the first longitudinal rod 3-2 by means of the second locking member 11. The second longitudinal rod 4-2 is arranged between the second transverse rod 4-1 and the ball head seat 5. The right end of the second transverse rod 4-1 can rotate around the first longitudinal rod 3-2 in a horizontal plane, so that the left end of the second transverse rod 4-1 drives the components located thereon to approach or move away from the operating table, so that the baffle 6 approaches or moves away from the patient's body. After adjustment, the second transverse rod 4-1 can be locked on the first longitudinal rod 3-2 by means of the second locking member 11. The structure is simple, the adjustment is convenient and quick, and time and labor saving are saved.

[0041] Furthermore, if Figure 1 As shown, it also includes a second rotating sleeve 12, which is arranged at one end of the second transverse rod 4-1 close to the first longitudinal rod 3-2. The second rotating sleeve 12 is sleeved on the outer periphery of the first longitudinal rod 3-2 and is rotatably connected thereto. The upper end of the first longitudinal rod 3-2 has a second supporting surface 13. The lower end of the second locking member 11 passes through the second rotating sleeve 12 and is threadedly connected to the first longitudinal rod 3-2. The second rotating sleeve 12 is clamped between the upper end of the second locking member 11 and the second supporting surface 13. The right end of the second transverse rod 4-1 is sleeved on the first longitudinal rod 3-2 through the second rotating sleeve 12. The outer diameter of the first longitudinal rod 3-2 located above the second supporting surface 13 is smaller than the diameter of the lower part, so that the second rotating sleeve 12 can be placed on the second supporting surface 13 after being sleeved from top to bottom to the outer periphery of the first longitudinal rod 3-2, and then the lower end of the second locking member 11 is passed through the second rotating sleeve 12 and threadedly connected with the first longitudinal rod 3-2. After adjusting the position of the second transverse rod 4-1, the second locking member 11 is screwed down to clamp the second rotating sleeve 12 between the upper end of the second locking member 11 and the second supporting surface 13. The structure is simple, the connection is firm and reliable, and the disassembly and assembly are convenient and fast, saving time and effort.

[0042] Furthermore, if Figure 1 As shown, it also includes a positioning sleeve 14 and a third locking member 15. The positioning sleeve 14 is arranged on the second angle adjustment rod 4, the axis of the positioning sleeve 14 is arranged horizontally, the ball head seat 5 is arranged coaxially with the positioning sleeve 14, and the ball head seat 5 is arranged on the second angle adjustment rod 4 with the help of the positioning sleeve 14; the third locking member 15 is threadedly connected with the positioning sleeve 14, and the ball head 7 is locked in the ball head seat 5 with the help of the third locking member 15, and the other end of the third locking member 15 is located outside the positioning sleeve 14. The angle of the baffle 6 can be adjusted by rotating the ball head 7 in the ball head seat 5. After the adjustment is completed, the third locking member 15 is rotated to lock the ball head 7 in the current position. The structure is simple, the adjustment is convenient and fast, and it saves time and effort.

[0043] Furthermore, if Figure 1 and Figure 2 As shown, the ball head 7 includes a ball 7-1 and a rod 7-2. The ball 7-1 is rotatably arranged in the ball head seat 5. The inner diameter of the end of the ball head seat 5 away from the positioning sleeve 14 is smaller than the diameter of the ball 7-1. The rod 7-2 is arranged between the ball 7-1 and the baffle 6. A notch 16 is provided on the end surface of the ball head seat 5 away from the positioning sleeve 14. The rod 7-2 is engaged with or separated from the notch 16 after rotation. Figure 1 As shown, the ball head seat 5 is located on the left side of the positioning sleeve 14, and the third locking piece 15 is located on the right side of the positioning sleeve 14. A notch 16 is opened on the left end face of the ball head seat 5 so that the rod body 7-2 can be set in the left-right direction or in the front-back direction. By changing the position of the rod body 7-2, the position of the baffle 6 can be changed, and the position and angle of the baffle 6 can be adjusted more flexibly.

[0044] Furthermore, if Figure 1 As shown, it also includes a locking rod 17. The fixing seat 1 is mounted on the operating bed. A mounting hole is provided on the fixing seat 1. The mounting hole is located outside the operating bed. A threaded hole is provided on the operating bed at a position corresponding to the mounting hole. One end of the locking rod 17 passes through the mounting hole and is threadedly connected to the threaded hole. The other end of the locking rod 17 is located outside the fixing seat 1. When installing, firstly put the fixing seat 1 on the operating bed, then pass the locking rod 17 through the mounting hole on the fixing seat 1 and be threadedly connected to the threaded hole on the operating bed, and then the fixing seat 1 can be locked on the operating bed. When disassembling, first separate the locking rod 17 from the operating bed, and then disassemble the fixing seat 1 from the operating bed. The structure is simple, the connection is firm and reliable, and the disassembly and assembly are convenient and quick, saving time and effort.

[0045] Furthermore, if Figure 1 As shown, an operating handle 18 is also included, and the operating handle 18 is arranged on the locking rod 17, and the operating handle 18 is arranged vertically with the locking rod 17. When the locking rod 17 needs to be rotated, the operating handle 18 can be held by hand, which is more convenient and comfortable.

[0046] Furthermore, if Figure 2 As shown, the baffle 6 has a fixing surface 19 and a supporting surface 20, the ball head 7 is arranged on the fixing surface 19, and the supporting surface 20 is an arcuate surface with the middle part concave toward the ball head 7. The arcuate surface enables the baffle 6 to better contact with the patient's body and better play the role of supporting and fixing the patient's body.

[0047] In this embodiment, the fixing seat 1 is locked on the operating table by the locking rod 17, the support rod 2 is arranged on the fixing seat 1, and the height of the support rod 2 can be adjusted. The right end of the first transverse rod 3-1 of the first angle adjustment rod 3 is sleeved on the support rod 2 through the first rotating sleeve 9, and the first rotating sleeve 9 can be locked between the first locking member 8 and the first supporting surface 10, the first longitudinal rod 3-2 is arranged on the left end of the first transverse rod 3-1, the right end of the second transverse rod 4-1 of the second angle adjustment rod 4 is sleeved on the first longitudinal rod 3-2 through the second rotating sleeve 12, and the second rotating sleeve 12 can be locked between the second locking member 11 and the second supporting surface 13, the second longitudinal rod 4-2 is arranged at the left end of the second transverse rod 4-1, and the positioning sleeve 14 is arranged at the upper end of the second longitudinal rod 4-2. The ball head seat 5 and the third locking member 15 are coaxially arranged with the positioning sleeve 14, the ball head seat 5 is located on one side of the positioning sleeve 14, and the third locking member 15 is located on the other side of the positioning sleeve 14, and the ball head 7 can be locked between the ball head seat 5 and the third locking member 15. The first angle adjustment rod 3 and the second angle adjustment rod 4 can both rotate horizontally, thereby changing the distance between the baffle 6 and the operating bed, which is more flexible and can increase the movable angle of the baffle 6, ensuring that the baffle 6 is in surface contact with the patient's body. The contact area is large enough, the support and fixation are more stable, and the patient is more comfortable.

[0048] It should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A surgical posture omnidirectional angle support frame, characterized in that: include, A fixing seat (1), the fixing seat (1) being used for being locked on the operating table; A support rod (2), the support rod (2) being arranged on the fixing seat (1); A first angle adjustment rod (3), one end of the first angle adjustment rod (3) being arranged on the support rod (2) and the other end of the first angle adjustment rod (3) being moved closer to or farther away from the operating bed after rotation; a second angle adjustment rod (4), one end of the second angle adjustment rod (4) being arranged on the first angle adjustment rod (3) and the other end of the second angle adjustment rod (4) being moved closer to or farther away from the operating table after rotation; A ball head seat (5), wherein the ball head seat (5) is arranged on the second angle adjustment rod (4); A baffle (6), wherein a ball head (7) is arranged on the baffle (6), the ball head (7) is rotatably arranged in the ball head seat (5), and the baffle (6) is used to contact the patient's body.

2. The all-round surgical posture support according to claim 1, characterized in that: It also includes a first locking member (8), and the first angle adjustment rod (3) includes: a first transverse rod (3-1), one end of the first transverse rod (3-1) being rotatably disposed on the support rod (2) and being locked with the support rod (2) by means of the first locking member (8); A first longitudinal rod (3-2), wherein the first longitudinal rod (3-2) is arranged between the first transverse rod (3-1) and the second angle adjustment rod (4).

3. The surgical posture omnidirectional angle support frame according to claim 2, characterized in that: The invention also comprises a first rotating sleeve (9), the first rotating sleeve (9) being arranged at one end of the first transverse rod (3-1) close to the support rod (2), the first rotating sleeve (9) being sleeved on the outer periphery of the support rod (2) and being rotatably connected thereto, the upper end of the support rod (2) having a first supporting surface (10), the lower end of the first locking member (8) passing through the first rotating sleeve (9) and being threadedly connected to the support rod (2), the first rotating sleeve (9) being clamped between the upper end of the first locking member (8) and the first supporting surface (10).

4. The all-round surgical posture support according to claim 2, characterized in that: It also includes a second locking member (11), and the second angle adjustment rod (4) includes: a second transverse rod (4-1), one end of the second transverse rod (4-1) being rotatably disposed on the first longitudinal rod (3-2) and being locked with the first longitudinal rod (3-2) by means of the second locking member (11); A second longitudinal rod (4-2), wherein the second longitudinal rod (4-2) is arranged between the second transverse rod (4-1) and the ball head seat (5).

5. The all-round surgical posture support according to claim 4, characterized in that: The invention also comprises a second rotating sleeve (12), the second rotating sleeve (12) being arranged at one end of the second transverse rod (4-1) close to the first longitudinal rod (3-2), the second rotating sleeve (12) being sleeved on the outer periphery of the first longitudinal rod (3-2) and being rotatably connected thereto, the upper end of the first longitudinal rod (3-2) having a second supporting surface (13), the lower end of the second locking member (11) passing through the second rotating sleeve (12) and being threadedly connected to the first longitudinal rod (3-2), the second rotating sleeve (12) being clamped between the upper end of the second locking member (11) and the second supporting surface (13).

6. The surgical posture omnidirectional angle support frame according to claim 1, characterized in that: Also includes, a positioning sleeve (14), the positioning sleeve (14) being arranged on the second angle adjustment rod (4), the axis of the positioning sleeve (14) being arranged horizontally, the ball head seat (5) being arranged coaxially with the positioning sleeve (14), and the ball head seat (5) being arranged on the second angle adjustment rod (4) by means of the positioning sleeve (14); A third locking piece (15), the third locking piece (15) is threadedly connected to the positioning sleeve (14), the ball head (7) is locked in the ball head seat (5) by means of the third locking piece (15), and the other end of the third locking piece (15) is located outside the positioning sleeve (14).

7. The surgical posture omnidirectional angle support frame according to claim 6, characterized in that: The ball head (7) comprises: A spherical body (7-1), the spherical body (7-1) being rotatably disposed in the spherical head seat (5), the inner diameter of an end of the spherical head seat (5) away from the positioning sleeve (14) being smaller than the diameter of the spherical body (7-1); A rod body (7-2) is arranged between the ball body (7-1) and the baffle (6), and a notch (16) is provided on the end surface of the ball head seat (5) away from the positioning sleeve (14). The rod body (7-2) is engaged with or separated from the notch (16) after rotation.

8. The all-round surgical posture support frame according to claim 1, characterized in that: It also comprises a locking rod (17), the fixing seat (1) being mounted on the operating bed, a mounting hole being provided on the fixing seat (1), the mounting hole being located outside the operating bed, a threaded hole being provided at a position on the operating bed corresponding to the mounting hole, one end of the locking rod (17) passing through the mounting hole and being threadedly connected to the threaded hole, and the other end of the locking rod (17) being located outside the fixing seat (1).

9. The surgical posture omnidirectional angle support frame according to claim 8, characterized in that: It also comprises an operating handle (18), wherein the operating handle (18) is arranged on the locking rod (17), and the operating handle (18) is arranged perpendicular to the locking rod (17).

10. The all-round surgical posture support frame according to claim 1, characterized in that: The baffle (6) has a fixing surface (19) and a supporting surface (20); the ball head (7) is arranged on the fixing surface (19); and the supporting surface (20) is an arc-shaped surface with a middle portion that is concave in the direction of the ball head (7).

Images