Hooke joint capable of being switched between two degrees of freedom and three degrees of freedom

Abstract

The utility model relates to the technical field of multi-degree-of-freedom platforms, in particular to a two-degree-of-freedom and three-degree-of-freedom switchable hooke joint, which comprises a first connecting piece, a second connecting piece, a third connecting piece and a fourth connecting piece, the second connecting piece is arranged on one side of the first connecting piece; the cross joint is connected between the first connecting piece and the second connecting piece, so that the second connecting piece can rotate along a first axis and a second axis relative to the first connecting piece; and the shaft piece is fixedly connected to the second connecting piece. On the basis of an original cross joint connecting structure, the shaft piece and the third connecting piece are arranged, the shaft piece, the third connecting piece and the cross joint connecting structure comprise two degrees of freedom, and two connecting states can be achieved between the shaft piece and the third connecting piece, so that the hooke joint can be applied to a motion platform with the two-degree-of-freedom requirement, and can also be applied to the motion platform with the two-degree-of-freedom requirement. And the device can also be applied to a motion platform with a three-degree-of-freedom requirement and is convenient to overhaul and maintain.

Description

Technical Field

[0001] The utility model relates to the technical field of multi-degree-of-freedom platforms, in particular to a Hooke's joint which is switchable between two degrees of freedom and three degrees of freedom. Background Art

[0002] Three-degree-of-freedom platforms are often used for some simple positioning, orientation and in-plane movement tasks. For example, educational displays, simulators (such as car driving simulators, train driving simulators, etc.), robot learning and other fields. Six-degree-of-freedom platforms are usually used in fields that require higher precision and more complex motion control due to their high precision and complex motion control capabilities. Such as flight simulators, ship simulators, surgical robots, 3D printing, spacecraft docking, aerial refueling docking, etc.

[0003] Generally, non-torsion-proof electric cylinders are usually used on three- and six-freedom platforms, and the connecting parts are two-degree-of-freedom Hook joints. If anti-torsion electric cylinders are used, only three-degree-of-freedom ball joints can be used. However, ball joints are difficult to process and costly, and are not suitable for large load applications.

[0004] Therefore, the three- and six-freedom platforms have different articulated parts when choosing different electric cylinders (anti-torsion and non-anti-torsion electric cylinders), and it is difficult to unify them, which makes it difficult to unify the platform shape and height. Utility Model Content

[0005] In view of the technical problems existing in the prior art Hooke's joint, the first aspect of the utility model proposes a Hooke's joint that can switch between two degrees of freedom and three degrees of freedom, including:

[0006] A first connecting member, used to connect to the moving platform of the multi-degree-of-freedom platform;

[0007] a second connecting member, disposed on one side of the first connecting member;

[0008] A cross-piece connected between the first connecting member and the second connecting member, so that the second connecting member can rotate relative to the first connecting member along the first axis and the second axis;

[0009] a shaft member fixedly connected to the second connecting member;

[0010] A third connecting member, used to be connected to the driving cylinder, the shaft member and the third connecting member have a first connection state and a second connection state;

[0011] Wherein, the shaft member and the third connecting member are fixed to each other when in the first connection state, and can rotate relative to each other along the third axis direction when in the second connection state, and the first axis, the second axis and the third axis are perpendicular to each other;

[0012] The shaft member and the third connecting member realize state switching between the first connection state and the second connection state through a locking structure. When the locking structure is connected to the shaft member and the third connecting member, the shaft member and the third connecting member are in the first connection state. When the locking structure is separated from the shaft member and the third connecting member, the shaft member and the third connecting member are in the second connection state.

[0013] Preferably, the shaft member and the third connecting member are provided with positioning holes arranged along the third axis direction, and the locking structure comprises bolts, and the bolts can be connected to the positioning holes on the shaft member and the third connecting member.

[0014] Preferably, the shaft member is constructed to include a first shaft section, a second shaft section and a third shaft section, the first shaft section is connected to the second connecting member, the third connecting member is constructed as a hollow cylinder, the third shaft section is connected to the third connecting member, and the second shaft section is constructed as a disc shape and aligned with the end face of the third connecting member.

[0015] Preferably, the second shaft segment is provided with a plurality of axial holes distributed in a centrally symmetrical manner, the third connecting member is provided with the blind hole at one end facing the second shaft segment, and the locking structure includes a bolt, which passes through the axial hole and is connected to the blind hole to fix the shaft member and the third connecting member.

[0016] Preferably, a bearing is provided between the shaft member and the third connecting member.

[0017] Preferably, the inner wall of the third connecting member is provided with an annular step, and the bearing includes a first deep groove ball bearing and a second deep groove ball bearing, the first deep groove ball bearing is located at the upper end of the annular step, and the second deep groove ball bearing is located at the lower end of the annular step, and a nut is provided at the bottom of the third shaft section, and the nut is pressed against the inner ring of the second deep groove ball bearing.

[0018] Preferably, the cross section comprises an airfoil cross section.

[0019] Preferably, the first connecting member is provided with a pair of first ears, the second connecting member is provided with a pair of second ears, and the cross-knot is rotatably connected to the first ears and the second ears.

[0020] Compared with the prior art, the advantages of the utility model are:

[0021] The utility model is based on the original cross-joint connection structure, and an axis member and a third connection member are arranged. The axis member and the third connection member, and the cross-joint connection structure include two degrees of freedom. Two connection states can be realized between the axis member and the third connection member, one is a fixed state, and the other is a movable connection state. When the axis member and the third connection member are in the fixed state, the Hooke's joint has only two degrees of freedom. When the axis member and the third connection member are in the movable connection state, the Hooke's joint has three degrees of freedom. Therefore, this Hooke's joint can be applied to a motion platform requiring two degrees of freedom, and can also be applied to a motion platform requiring three degrees of freedom, and helps to maintain a unified shape, and is convenient for inspection and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For the sake of clarity, not every component is labeled in each figure. Now, embodiments of various aspects of the utility model will be described by way of example and with reference to the accompanying drawings, in which:

[0023] Figure 1 It is a schematic structural diagram of a two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint shown in the utility model;

[0024] Figure 2 It is a schematic diagram of the cross-sectional structure shown in the utility model;

[0025] Figure 3 It is a schematic cross-sectional structure diagram of the third connecting member shown in the utility model;

[0026] Figure 4 It is a schematic diagram of the structure of a ten-byte structure shown in the utility model. DETAILED DESCRIPTION

[0027] In order to better understand the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.

[0028] like Figure 1 As shown, the first aspect of the utility model provides a two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint, comprising a first connecting member 10 , a second connecting member 20 , a cross member 30 , an axis member 40 and a third connecting member 50 .

[0029] The first connecting member 10 and the second connecting member 20 are respectively the upper connecting member and the lower connecting member of the cross-section. The first connecting member 10 is used to connect to the moving platform of the multi-degree-of-freedom platform. The second connecting member 20 is arranged on one side of the first connecting member 10. The cross-section 30 is connected between the first connecting member 10 and the second connecting member 20, so that the second connecting member 20 can rotate relative to the first connecting member 10 along the first axis and the second axis.

[0030] In this way, there are two degrees of freedom between the first connecting member 10 and the second connecting member 20, namely, the degree of freedom of rotation about the first axis and the degree of freedom of rotation about the second axis.

[0031] Further, the shaft member 40 is fixedly connected to the second connecting member 20, and the third connecting member 50 is used to be connected to the driving cylinder. The shaft member 40 and the third connecting member 50 have a first connection state and a second connection state.

[0032] In particular, when the shaft member 40 and the third connecting member 50 are in the first connection state, they are fixed to each other, and when the shaft member 40 and the third connecting member 50 are in the second connection state, they can rotate relative to each other along the third axis direction, and the first axis, the second axis, and the third axis are perpendicular to each other.

[0033] Among them, the shaft member 40 and the third connecting member 50 realize state switching between the first connection state or the second connection state through the locking structure 60. When the locking structure 60 is connected to the shaft member 40 and the third connecting member 50, the shaft member 40 and the third connecting member 50 are in the first connection state. When the locking structure 60 is separated from the shaft member 40 and the third connecting member 50, the shaft member 40 and the third connecting member 50 are in the second connection state.

[0034] In this way, the state switching between the shaft member 40 and the third connecting member 50 is achieved through the locking structure 60, and the connection structure is switched between two degrees of freedom and three degrees of freedom. When two degrees of freedom are needed, the shaft member 40 and the third connecting member 50 can be locked by the locking structure 60 to make them relatively fixed, and only two degrees of freedom are retained between the first connecting member 10 and the second connecting member 20. When three degrees of freedom are needed, the locking structure 60 can be separated. At this time, the shaft member 40 and the third connecting member 50 can rotate relative to each other along the third axis to achieve three degrees of freedom.

[0035] like Figure 1 and Figure 4 As shown, the cross member 30 comprises an airfoil cross member. A pair of first ears 31 are provided on the first connecting member 10, a pair of second ears 32 are provided on the second connecting member 20, and the cross member 30 is rotatably connected with the first ears 31 and the second ears 32.

[0036] like Figure 2-3 As shown, the shaft member 40 and the third connecting member 50 are provided with positioning holes arranged along the third axis direction, and the locking structure 60 includes bolts, which can be connected to the positioning holes on the shaft member 40 and the third connecting member 50.

[0037] In this way, after the bolts are passed through the positioning holes of the shaft member 40 and the third connecting member 50, the shaft member 40 and the third connecting member 50 are locked, and the bolts can withstand a larger shear force to resist the shear force caused by the relative rotation of the shaft member 40 and the third connecting member 50, thereby keeping the shaft member 40 and the third connecting member 50 reliably fixed.

[0038] In an alternative embodiment, if Figure 3 As shown, the shaft member 40 is constructed to include a first shaft segment 41, a second shaft segment 42 and a third shaft segment 43, the first shaft segment 41 is fixedly connected to the second connecting member 20, the third connecting member 50 is constructed as a hollow cylinder, the third shaft segment 43 is connected to the third connecting member 50, and the second shaft segment 42 is constructed as a disc shape, aligned with the end face of the third connecting member 50.

[0039] Furthermore, a bearing 51 is provided between the shaft member 40 and the third connecting member 50 .

[0040] Specifically, the inner wall of the third connecting member 50 is provided with an annular step, and the bearing 51 includes a first deep groove ball bearing and a second deep groove ball bearing. The first deep groove ball bearing is located at the upper end of the annular step, and the second deep groove ball bearing is located at the lower end of the annular step. A nut 45 is provided at the bottom of the third shaft section 43, and the nut 45 is pressed against the inner ring of the second deep groove ball bearing.

[0041] In this way, the third shaft segment 43 can be inserted into the inner wall of the third connecting member 50. During assembly, the first deep groove ball bearing is placed on the upper end of the annular step, and then the third shaft segment 43 is inserted into the inner wall of the third connecting member 50 so that its end passes through the annular step. The second deep groove ball bearing is placed on the outer wall of the third shaft segment 43, and then the nut 45 is tightened at the bottom of the third shaft segment 43 to complete the assembly of the third shaft segment 43 and the third connecting member 50.

[0042] Optionally, the second shaft segment 42 is provided with a plurality of axial holes 44 distributed in a centrally symmetrical manner, and the third connecting member 50 is provided with a blind hole 12 at one end facing the second shaft segment 42. The locking structure 60 includes a bolt, which passes through the axial hole 44 and is connected to the blind hole 12 to fix the shaft member 40 and the third connecting member 50.

[0043] In this way, the shaft member 40 and the third connecting member 50 can be reliably connected by a plurality of bolts.

[0044] In combination with the above embodiments, the utility model is based on the original cross-connection structure, and an axis member and a third connection member are arranged. The axis member and the third connection member, the cross-connection structure includes two degrees of freedom, and two connection states can be realized between the axis member and the third connection member, one is a fixed state, and the other is an active connection state. When the axis member and the third connection member are in a fixed state, the Hooke's joint has only two degrees of freedom. When the axis member and the third connection member are in an active connection state, the Hooke's joint has three degrees of freedom. Therefore, this Hooke's joint can be used in motion platforms requiring two degrees of freedom, and can also be used in motion platforms requiring three degrees of freedom, and it helps to maintain a unified shape and facilitates inspection and maintenance.

[0045] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint, characterized in that: include: A first connecting member (10) is used to connect to a moving platform of the multi-degree-of-freedom platform; A second connecting member (20) is arranged on one side of the first connecting member (10); A crosspiece (30) connected between the first connecting member (10) and the second connecting member (20) so that the second connecting member (20) can rotate relative to the first connecting member (10) along the first axis and the second axis; A shaft member (40) fixedly connected to the second connecting member (20); A third connecting member (50) is used to be connected to the driving cylinder, the shaft member (40) and the third connecting member (50) having a first connection state and a second connection state; The shaft member (40) and the third connecting member (50) are fixed to each other when in a first connection state, and can rotate relative to each other along a third axis when in a second connection state, and the first axis, the second axis, and the third axis are perpendicular to each other; The shaft member (40) and the third connecting member (50) realize state switching between a first connection state and a second connection state through a locking structure (60); when the locking structure (60) is connected to the shaft member (40) and the third connecting member (50), the shaft member (40) and the third connecting member (50) are in the first connection state; when the locking structure (60) is separated from the shaft member (40) and the third connecting member (50), the shaft member (40) and the third connecting member (50) are in the second connection state.

2. The two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint according to claim 1, characterized in that: The shaft member (40) and the third connecting member (50) are provided with positioning holes arranged along the third axis direction, and the locking structure (60) comprises bolts, which can be connected to the positioning holes on the shaft member (40) and the third connecting member (50).

3. The two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint according to claim 1, characterized in that: The shaft member (40) is constructed to include a first shaft section (41), a second shaft section (42) and a third shaft section (43); the first shaft section (41) is connected to the second connecting member (20); the third connecting member (50) is constructed to be a hollow cylinder; the third shaft section (43) is connected to the third connecting member (50); the second shaft section (42) is constructed to be disc-shaped and aligned with an end face of the third connecting member (50).

4. The two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint according to claim 3, characterized in that: The second shaft section (42) is provided with a plurality of shaft holes (44) distributed symmetrically with respect to the center, the third connecting member (50) is provided with a blind hole (12) at one end facing the second shaft section (42), and the locking structure (60) comprises a bolt, which passes through the shaft hole (44) and is connected to the blind hole (12) to fix the shaft member (40) and the third connecting member (50).

5. The two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint according to claim 3, characterized in that: A bearing (51) is provided between the shaft member (40) and the third connecting member (50).

6. The two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint according to claim 5, characterized in that: An inner wall of the third connecting member (50) is provided with an annular step, the bearing (51) comprises a first deep groove ball bearing and a second deep groove ball bearing, the first deep groove ball bearing is located at the upper end of the annular step, the second deep groove ball bearing is located at the lower end of the annular step, and a nut (45) is provided at the bottom of the third shaft section (43), the nut (45) being pressed against the inner ring of the second deep groove ball bearing.

7. The two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint according to claim 1, characterized in that: The ten bytes (30) include an airfoil ten bytes.

8. The two-degree-of-freedom and three-degree-of-freedom switchable Hooke's joint according to claim 1, characterized in that: The first connecting member (10) is provided with a pair of first ears (31), the second connecting member (20) is provided with a pair of second ears (32), and the cross-piece (30) is rotatably connected to the first ears (31) and the second ears (32).

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