CN115182974A - A twist-proof multi-degree-of-freedom linkage mechanism - Google Patents

Abstract

The invention relates to an anti-torsion multi-degree-of-freedom connecting rod mechanism, which comprises a connecting rod and a guide device, wherein the connecting rod is connected with the guide device; at least one end of two axial ends of the connecting rod is provided with a hinged part which can rotate around a spherical center, and the spherical center is positioned on the axis of the connecting rod; the guide device comprises a guide groove arranged along the axial direction of the connecting rod, a guide piece and a guide connecting piece, wherein the guide piece is positioned in the guide groove and can slide along the guide groove, the guide piece is rigidly connected with the connecting rod through the guide connecting piece, and the central axis of the guide piece always passes through the spherical center of the hinged piece and the central axis of the guide piece always coincides with the central plane of the guide groove.

Description

A twist-proof multi-degree-of-freedom linkage mechanism

technical field

The invention relates to the technical field of mechanical connection, in particular to a multi-degree-of-freedom linkage mechanism with anti-twist.

Background technique

In many mechanical structures, connecting rods are used as transmission parts, such as ball joints or rod end bearings at both ends of the connecting rod. When the rod end bearing is used, since the rod end bearing is not allowed to have a large inclination angle in individual directions, the connecting rod is not allowed to have a large torsional motion. Although the ball joint allows rotation in all directions, if there is a sensor on the connecting rod, in order to protect the wiring harness of the sensor, or due to space constraints, the connecting rod is not allowed to have a large torsional motion.

In order to avoid a large torsional motion of the connecting rod, the prior art generally uses a guide device to limit the degree of freedom of the connecting rod. As shown in FIGS. 1-3 , a connecting rod mechanism in the prior art connects the connecting rod 101 and the piston rod 103 through the rod end bearing 102 , and the guide device includes a guide bearing 203 located in a guide groove 204 and a The connecting rod 101 is rigidly connected to the fixed rod 201 , the guide bearing 203 is fixed on the fixed rod 201 by the nut 202 , the guide bearing 203 can move in the guide groove 204 , and the center axis of the guide bearing 203 always coincides with the center plane of the guide groove 204 . When the link mechanism is in operation, the link 101 can move along the X1 axis, and at the same time, it can swing up and down at a certain angle around the Y1 axis with the rod end bearing 102 as the center.

The above-mentioned guide device restricts the link mechanism from the above movement, and the link 101 cannot exhibit other movement forms, such as swinging around the Z1 axis with the rod end bearing 102 as the center. However, if the guide device is not used, the connecting rod 101 will be freely twisted at a certain angle around the X1 axis when moving. The rod end bearing 102 generally allows the connecting rod 101 to rotate at a certain angle in the direction of the X1 axis (eg ±5°). If the angle exceeds the limit, it may collide with the rod end bearing itself or scratch the surface of the steel ball inside the rod end bearing. If the collision or spherical surface scratches, it will cause great damage to the rod end bearing. In addition, there may be electronic components such as sensors on the connecting rod 101. Considering the protection of the wiring harness or avoiding bumps, the connecting rod 101 may not be allowed to have an excessively large free twist angle.

Therefore, the existing general guide device has relatively large restrictions on the freedom of movement of the connecting rod, and is not suitable for a connecting rod structure with more flexible movement in space.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a meter that allows the connecting rod to swing at a certain angle around the Y-axis and the Z-axis at the same time when the connecting rod moves axially along the X-axis, and the connecting rod itself will not be twisted during operation. Torsional multi-degree-of-freedom linkage.

For achieving the above object, the technical scheme adopted in the present invention is as follows:

An anti-twist multi-degree-of-freedom linkage mechanism, comprising a connecting rod and a guide device;

At least one of the two axial ends of the connecting rod is provided with a hinge, the hinge can rotate around a spherical center, and the spherical center is located on the axis of the connecting rod;

The guide device includes a guide groove opened along the axial direction of the connecting rod, a guide member located in the guide groove and capable of sliding along the guide groove, and a guide connecting member, and the guide member is rigidly connected to the connecting rod through the guide connecting member connected, and the central axis of the guide piece always passes through the spherical center of the hinge piece and the central axis of the guide piece always coincides with the central plane of the guide groove. Since the central axis of the guide always passes through the ball center of the hinge, the connecting rod can swing at a certain angle around the Y axis and the Z axis, and since the central axis of the guide always moves in the center plane of the guide groove, at any In the case of action, the connecting rod will not twist around its own axis.

In an embodiment, the guide member and the hinge member are disposed in a radial direction of the connecting rod.

In one embodiment, the guide connecting piece includes a fixing rod and an extension plate, the fixing rod is extended along the radial direction of the connecting rod, and one end of the fixing rod is rigidly connected with the middle of the connecting rod, The other end is fixedly connected with the extension plate, the extension plate is extended along the axial direction of the connecting rod, and the extension plate is fixedly connected with the guide member.

In one embodiment, the guide member is a bearing, and the central axis of the bearing always passes through the ball center of the hinge member and the central axis of the bearing always coincides with the central plane of the guide groove.

In an embodiment, a bearing support is further included, the bearing support has a cylinder matched with the inner ring of the bearing, and the bearing is fixed on the cylinder.

In one embodiment, a shoulder to prevent the bearing from coming out of the cylinder is further provided on one end in the axial direction of the cylinder, and a shoulder on the other end in the axial direction of the cylinder is fixedly installed. A tab that prevents the bearing from coming out of the cylinder.

In one embodiment, the guide link is fixedly connected to the bearing support.

In one embodiment, the guide groove includes two side walls arranged opposite to each other, and the peripheral surface of the outer ring of the bearing is in abutting contact with the two side walls.

In one embodiment, when the connecting rod moves, the peripheral surface of the outer ring of the bearing maintains a state of abutting contact with both side walls of the guide groove.

In one embodiment, the hinge is a rod end bearing or a ball hinge.

The present invention adopts the above technical scheme, and has the beneficial effect that the anti-twist multi-degree-of-freedom link mechanism provided by the present invention always passes through the center axis of the guide piece through the ball center of the hinge piece, so the connecting rod can surround the Y-axis and the Z-axis. The shafts swing at a certain angle, and since the central axis of the guide piece always moves within the central plane of the guide groove, the connecting rod will not twist around its own axis under any action conditions.

Description of drawings

FIG. 1 shows a schematic perspective view of a link mechanism in the prior art.

FIG. 2 shows a front view of a linkage mechanism in the prior art.

Fig. 3 shows a schematic diagram of a guide device of a link mechanism in the prior art.

FIG. 4 shows a schematic perspective view of the multi-degree-of-freedom linkage mechanism provided by the present invention.

FIG. 5 shows a front view of the multi-degree-of-freedom linkage mechanism provided by the present invention.

FIG. 6 shows a side view of the multi-degree-of-freedom linkage mechanism provided by the present invention.

FIG. 7 shows a schematic cross-sectional view of the guide device of the multi-degree-of-freedom linkage mechanism provided by the present invention.

FIG. 8 is a schematic perspective view of the guide device of the multi-degree-of-freedom linkage mechanism provided by the present invention.

Detailed ways

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so as to more clearly understand the objects, features and advantages of the present invention. It should be understood that the embodiments shown in the accompanying drawings are not intended to limit the scope of the present invention, but are only intended to illustrate the essential spirit of the technical solutions of the present invention.

In the following description, for the purpose of illustrating various disclosed embodiments, certain specific details are set forth in order to provide a thorough understanding of the various disclosed embodiments. One skilled in the relevant art will recognize, however, that the embodiments may be practiced without one or more of these specific details. In other instances, well-known devices, structures and techniques associated with this application may not be shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

Unless the context requires otherwise, throughout the specification and claims, the word "comprising" and variations thereof, such as "comprising" and "having", should be construed in an open, inclusive sense, i.e., should be interpreted as "including, but not limited to".

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of "in one embodiment" or "in an embodiment" in various places throughout the specification are not necessarily all referring to the same embodiment. Additionally, the particular features, structures or characteristics may be combined in any manner in one or more embodiments.

As used in this specification and the appended claims, the singular forms "a" and "the" include plural referents unless the context clearly dictates otherwise. It should be noted that the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

In the following description, in order to clearly show the structure and working mode of the present invention, many directional words will be used for description, but "front", "rear", "left", "right", "outer", "inner" should be "," "outward", "inward", "up", "down" and other words are to be understood as convenient terms, and should not be understood as limiting words.

Furthermore, the terms "horizontal", "vertical", "overhanging" etc. do not imply that a component is required to be absolutely horizontal or overhang, but rather may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal than "vertical", it does not mean that the structure must be completely horizontal, but can be slightly inclined.

In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "arrangement", "installation", "connection" and "connection" should be interpreted in a broad sense, for example, it may be a fixed connection, It can also be a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in specific situations.

The utility model provides an anti-twist multi-degree-of-freedom link mechanism, which comprises a connecting rod and a guide device. At least one end of the two axial ends of the connecting rod is provided with a hinge piece, and the hinge piece can wrap around a spherical center. rotate, and the ball center is located on the axis of the connecting rod; the guide device includes a guide groove opened along the axial direction of the connecting rod and a guide member located in the guide groove and capable of sliding along the guide groove, the guide member is guided by the guide The connecting piece is rigidly connected with the connecting rod, and the central axis of the guiding piece always passes through the spherical center of the hinge piece and the central axis of the guiding piece always coincides with the central plane of the guiding groove.

As shown in FIGS. 4-7 , this embodiment provides an anti-twist multi-degree-of-freedom link mechanism, including a link and a guide device. Among them, the axial direction of the piston rod 303 is used as the X2 axis to define a three-axis coordinate system with the X2 axis, the Y2 axis, and the Z2 axis as the axial directions, and the rear end of the connecting rod 301 is rigidly connected with a rod end bearing as a hinge. 302 , the connecting rod 301 is hingedly connected with the external mechanism through the rod end bearing 302 . For example, in this embodiment, the connecting rod 301 is hingedly connected with the piston rod 303 through the rod end bearing 302 . The rod end bearing 302 includes a rod end joint bearing seat 3021 and a spherical sliding bearing 3022 mounted on the eye-shaped top end of the rod end joint bearing seat, and the spherical sliding bearing 3022 has a spherical center A. The axial end of the connecting rod 301 has a U-shaped groove 3011 matched with the spherical sliding bearing 3022, the hinged end of the rod end bearing 302 extends into the U-shaped groove 3011, and the spherical sliding bearing 3022 of the rod end bearing 302 The connecting rod 301 is fixedly mounted on the connecting rod 301 by a fixing pin 3023 arranged along the radial direction of the connecting rod 301 , so that the connecting rod 301 can be hinged around the ball center A of the spherical sliding bearing 3022 . It is defined that the axial direction of the fixing pin 3023 is arranged along the Y2 axis direction. It should be noted here that the hinge is not limited to the rod end bearing 302, and other hinges that can achieve the same function are also applicable here, such as a ball joint.

The guiding device includes a guiding groove 401 , a guiding piece and a guiding connecting piece 403 . The guide groove 401 extends along the X2 axis direction, and the center plane B of the guide groove 401 coincides with the axis of the piston rod 303 . The guide groove 401 in this embodiment includes two guide plates 4010 disposed opposite to each other, and the opposite inner side walls of the two guide plates 4010 are the two side walls of the guide groove 401 .

The guide member is located in the guide groove 401, and can move along the X2 axis direction in the guide groove 401 and rotate around the central axis of the guide member itself. The central axis C of the guide always passes through the center of the sphere of the hinge. The guide in this embodiment is the bearing 402 , and the central axis C of the bearing 402 always passes through the ball center A of the spherical sliding bearing 3022 .

Referring to FIGS. 7 and 8 , at least one bearing 402 is secured to bearing support 404 . The bearing support 404 has a cylinder 4041 matched with the inner ring of the bearing 402 , and one axial end of the cylinder 4041 is further provided with a shoulder 4042 to prevent the bearing 402 from falling out of the cylinder 4041 . In this embodiment, the number of the bearings 402 is two, but is not limited to this. The number of the bearings 402 can be increased or decreased according to actual needs, for example, one or three or more than three. A spacer 405 is placed between the two bearings 402 , and the above-mentioned two bearings 402 and spacer 405 are fixed on the bearing support 404 through the pressure plate 406 and the bolt 407 on the other axial end of the cylinder 4041 . The outer ring of the bearing 402 is in contact with the two side walls of the guide groove 401 extending along the X2 axis direction, so that the bearing 402 can move along the X2 axis direction in the guide groove 401 .

One end of the guide connecting piece 403 is fixedly connected with the guide piece, and the other end is rigidly connected with the connecting rod 301 , so that the connecting rod 301 drives the guide piece to move in the guide groove 401 through the guide connecting piece 403 .

The multi-degree-of-freedom linkage mechanism in this embodiment can realize the following movements:

(1) The connecting rod 301 can move along the X2 axis of the X2Y2Z2 three-axis coordinate system. At this time, the guide member moves along the X2 axis direction in the guide groove 401 .

(2) The connecting rod 301 can swing up and down at a certain angle around the Y2 axis with the rod end bearing 302 as the center. Swing, as long as the guide piece is not detached from the guide groove, the up and down swing is within its allowable range of motion. At this time, the guide piece will deflect in the guide groove 401 corresponding to the swing range of the link 301 .

(3) The connecting rod 301 can rotate at a certain angle around the central axis C of the guide, that is, the connecting rod 301 can take the ball center A of the rod end bearing 302 as the end point and swing at a certain angle in the direction of the Y2 axis. The center axis C of the piece always coincides with the center plane B of the guide groove 401. Within the allowable range of the swing angle of the rod end bearing, as long as the guide connecting piece 403 does not collide with the two side walls of the guide groove 401, the connecting rod 301 can go around the guide groove 401. The center axis C of the guide swings freely in the left-right direction.

(4) While the connecting rod 301 can swing around the central axis C of the guide, the connecting rod 301 can also swing up and down at a certain angle around the Y2 axis with the rod end bearing 302 as the center. At this time, the connecting rod 301 can also Move along the X2 axis.

In order to ensure that the connecting rod 301 realizes the above-mentioned action, when the connecting rod 301 is moving, the peripheral surface of the outer ring of the bearing 402 maintains a state of abutting contact with the two side walls of the guide groove 401 .

In all the above motion states: since the central axis C of the guide member always moves in the central plane B of the guide groove 401, the connecting rod 301 will not twist around its own axis under any action condition. Therefore, during operation, since the connecting rod 301 itself will not be twisted, it will not cause uncontrolled free deflection of the connecting rod 301 and the rod end bearing 302, which can effectively protect the rod end bearing 302 or the rod end bearing 302 connected thereto. sensors, etc.

In one embodiment, referring to FIG. 7 and FIG. 8 , the guide member is disposed opposite to the hinge member to facilitate the assembly of the guide member while ensuring that the central axis C of the guide member always passes through the spherical center of the hinge member. The guide connector 403 in this embodiment includes a fixed rod 4031 and an extension plate 4032, wherein the fixed rod 4031 is extended along the Z2 axis direction, one end of which is rigidly connected to the middle of the connecting rod 301 by welding, and the other end is welded, The extension plate 4032 is fixed on the extension plate 4032 by means of nut locking. The extension plate 4032 is extended along the X2 axis direction, and the extension plate 4032 is fixed with the bearing support 404 by the bolts 407. The extension plate 4032 extends along the X2 axis direction to serve as a guide. The bearing 402 is located just below the rod end bearing 302 to facilitate the positioning and assembly of the bearing 402.

The preferred embodiments of the present invention have been described in detail above, but it should be understood that those skilled in the art can make various changes or modifications to the present invention after reading the above teaching contents of the present invention. Such equivalents also fall within the scope defined by the claims appended hereto.

Claims (10)

1. The utility model provides an anti-twist multi freedom link mechanism which characterized in that: comprises a connecting rod and a guide device;

at least one end of two axial ends of the connecting rod is provided with a hinge piece, the hinge piece can rotate around a spherical center, and the spherical center is positioned on the axis of the connecting rod;

the guide device comprises a guide groove arranged along the axial direction of the connecting rod, a guide piece and a guide connecting piece, wherein the guide piece is positioned in the guide groove and can slide along the guide groove, the guide piece is rigidly connected with the connecting rod through the guide connecting piece, and the central axis of the guide piece always passes through the spherical center of the hinged piece and the central axis of the guide piece always coincides with the central plane of the guide groove.

2. The multiple degree of freedom linkage mechanism of claim 1, wherein: the guide piece and the hinge piece are arranged just opposite to each other in the radial direction of the connecting rod.

3. The multiple degree of freedom linkage mechanism of claim 2, wherein: the direction connecting piece includes dead lever and extension plate, the dead lever is followed the radial direction of connecting rod extends the setting, the one end of dead lever with the middle part rigid connection of connecting rod, the other end with extension plate fixed connection, the extension plate is followed the axial direction of connecting rod extends the setting, just the extension plate with guide fixed connection.

4. The multiple degree of freedom linkage mechanism of claim 1, wherein: the guide piece is a bearing, and the central axis of the bearing always passes through the spherical center of the hinged piece and the central axis of the bearing always coincides with the central plane of the guide groove.

5. The multiple degree of freedom linkage mechanism of claim 4, wherein: the bearing support is provided with a cylinder matched with the inner ring of the bearing, and the bearing is fixed on the cylinder.

6. The multiple degree of freedom linkage mechanism of claim 5, wherein: the end part of one axial side of the cylinder is also provided with a convex shoulder for preventing the bearing from falling out of the cylinder, and the end part of the other axial side of the cylinder is fixedly provided with a pressing sheet for preventing the bearing from falling out of the cylinder.

7. The multiple degree of freedom linkage mechanism of claim 5, wherein: the guide connecting piece is fixedly connected with the bearing support.

8. The multiple degree of freedom linkage mechanism of claim 4, wherein: the guide groove comprises two side walls which are arranged oppositely, and the peripheral surface of the outer ring of the bearing is abutted against the two side walls.

9. The multiple degree of freedom linkage mechanism of claim 8, wherein: when the connecting rod acts, the peripheral surface of the outer ring of the bearing is kept in contact with the two side walls of the guide groove.

10. The multiple degree of freedom linkage mechanism of claim 1, wherein: the articulated piece is a rod end bearing or a ball joint.

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