Length-adjustable stress application mechanism

Abstract

The invention discloses a length-adjustable force application mechanism which comprises a rotating wedge ring and two connecting rings, the two connecting rings are rotationally arranged at the two axial ends of the rotating wedge ring in a sleeving mode respectively, the two connecting rings and the rotating wedge ring are coaxial, at least one spiral face is arranged on at least one of the upper end face and the lower end face of the rotating wedge ring, and the two connecting rings are connected with an external mechanism. The two connecting rings get close to each other under the action of external force, the end faces of the rotating wedge rings and the end faces of the connecting rings are matched, matched and contacted, the rotating wedge rings are rotated by applying torque to enable the two connecting rings to be gradually away from each other in the axial direction, and the end faces of the rotating wedge rings and the end faces of the connecting rings are at least partially contacted all the time. The rotary wedge ring is arranged to be screwed with the two connecting rings, the spiral surface is arranged on the contact end face, the purpose of adjusting the distance between the two connecting rings is achieved through the spiral surface, high-precision position adjustment can be achieved, position locking can be achieved through self-locking or torque keeping, and the large force application effect is achieved through small torque.

Description

Technical Field

[0001] The invention belongs to the technical field of pre-tightening and clamping, and in particular relates to a force-adding mechanism with adjustable length. Background Art

[0002] Common force loading mechanisms include screw-nut pairs and hydraulic cylinders. Since the root of the screw-nut pair has a small force-bearing surface, it will be subjected to large shear stress under heavy load, and shear failure often occurs at the root. The piston rod of the hydraulic cylinder usually has only two extreme positions: forward and backward under the action of oil pressure. If the extension distance of the piston rod needs to be adjusted, a complex control oil circuit system is required, and the use and maintenance costs of the hydraulic oil are also high.

[0003] In view of this, the present invention is proposed. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a force-adding mechanism with adjustable length.

[0005] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0006] A force-adding mechanism with adjustable length comprises a rotating wedge ring and two connecting rings, wherein the two connecting rings are respectively rotatably sleeved on the axial ends of the rotating wedge ring and the three are coaxial.

[0007] At least one of the upper and lower end faces of the rotating wedge ring is provided with at least one spiral surface. The two connecting rings are connected to an external mechanism and approach each other under the action of an external force. The end face of the rotating wedge ring matches and contacts with the end face of the connecting ring.

[0008] Applying torque to rotate the rotating wedge ring will cause the two connecting rings to gradually move away from each other in the axial direction, and the end surface of the rotating wedge ring is always at least partially in contact with the end surface of the connecting ring.

[0009] Furthermore, the radial section of the spiral surface is a straight line segment, an oblique line segment, a curved line segment, a broken line segment, and an arc segment.

[0010] Furthermore, there are multiple helical surfaces located on the same end face, and the lead angles α of the helical surfaces are consistent.

[0011] Furthermore, the number of helical faces n on the same end face has the following relationship with the helical face lead angle α, the helical face mid-diameter d, and the helical face height difference a:

[0012]

[0013] Moreover, when the lift angle α is smaller than the friction angle, the two connecting rings will be in a self-locking state.

[0014] Furthermore, a copper sliding plate for reducing friction is provided between the end surface of the rotating wedge ring and the end surface of the connecting ring.

[0015] Furthermore, grooves and protrusions for applying torque are provided on the circumferential outer wall of the rotating wedge ring.

[0016] Furthermore, gears and pulleys are provided on the circumferential outer wall of the rotating wedge ring.

[0017] After adopting the above technical scheme, the present invention has the following beneficial effects compared with the prior art.

[0018] The present invention provides a rotating wedge ring that is screwed together with two connecting rings, and provides a spiral surface on the contact end surface. The spiral surface is used to adjust the distance between the two connecting rings, thereby realizing high-precision position adjustment, and can realize position locking through self-locking or holding torque, and realize a large force effect with a small torque. Compared with the traditional hydraulic control system, the present invention has a simple structural design, strong practicality, low cost and long service life.

[0019] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are part of this application and are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the drawings described below are only some embodiments. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1 It is a schematic structural diagram of an embodiment of the present invention;

[0022] Figure 2 It is a structural schematic diagram of another embodiment of the present invention;

[0023] Figure 3 Schematic diagram of the present invention when the number of helical surfaces n on the same end face is 1, 2, and 3 respectively;

[0024] Figure 4 It is a schematic structural diagram of the spiral surface of the present invention when radially sectioned into broken line segments and arc segments;

[0025] Figure 5 Schematic diagram of the rise angle of the helicoid of the present invention.

[0026] In the figure: 1, rotating wedge ring; 2, connecting ring; 21, connecting ring one; 22, connecting ring two; 31, gear; 32, groove; 4, copper slide plate.

[0027] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0029] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0030] In the description of the present invention, 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 an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] Example

[0032] like Figures 1 to 5 As shown, the force-adding mechanism with adjustable length described in this embodiment includes a rotating wedge ring 1 and two connecting rings 2. The two connecting rings 2 are respectively rotatably sleeved on the axial ends of the rotating wedge ring 1, and the three are coaxial. Specifically, it is composed of a rotating wedge ring 1 and two connecting rings 2. The two connecting rings 2 are coaxially sleeved with the rotating wedge ring 1 from both ends. The connecting ring 2 is connected to the outer mechanism and does not rotate around the axis. The rotating wedge ring 1 rotates around the axis, and the two connecting rings 2 are coaxially arranged with the rotating wedge ring 1.

[0033] At least one of the upper and lower end faces of the rotating wedge ring 1 is provided with at least one helical surface, and the end face of the rotating wedge ring 1 is matched and in contact with the end face of the connecting ring 2. The upper and lower end faces of the rotating wedge ring 1 are provided with a helical surface, and at least one of the end faces is provided with one, and the end face of the connecting ring 2 is matched and in contact with it. For example, if the upper end face of the rotating wedge ring 1 has a helical surface and the lower end face is a plane, then the upper connecting ring 1 21 is also provided with a corresponding helical surface, and the lower connecting ring 2 22 is also a corresponding plane. The contact surface of the rotating wedge ring 1 and the connecting ring 2 is set to a spiral ascending surface with the same ascending angle, which can be a plane or a curved surface of any shape, that is, the radial section of the helical surface is a straight line segment, an oblique line segment, a curved line segment, a broken line segment, or an arc segment, see the attached Figure 3 The diagram is a straight line segment. When the spiral surface is an inclined surface or a curved surface, its radial section is an inclined line segment or a curved line segment. Figure 4 The diagram shows a triangular track and a circular arc track, where the radial sections of the spiral surface are broken line segments and arc segments. The shape of this type of track can also ensure that the three rings are concentric and are not prone to misalignment. The track can also play a role in limiting and guiding during rotation.

[0034] The two connecting rings 2 are connected to an external mechanism and approach each other under the action of external force. Applying torque to rotate the rotating wedge ring 1 will cause the two connecting rings 2 to gradually move away from each other in the axial direction, and the end face of the rotating wedge ring 1 is always at least partially in contact with the end face of the connecting ring 2. The attached figure shows that the two connecting rings 2 are both subjected to the pressure of the external connecting mechanism. The two connecting rings will approach each other due to the external pressure, and a torque will be applied to the rotating wedge ring 1. During rotation, the relative distance between the end faces of the two outer connecting rings will increase, achieving the effect of adjusting the distance. When the spacing adjustment of the outer mechanism is completed and the spacing is fixed, the torque continues to be applied to the rotating wedge ring 1, and the mechanism will apply thrust to both sides, and the two connecting rings will continue to have a tendency to separate from each other.

[0035] Any number of spiral surfaces can be set on the same end face, such as two, three, etc. ( Figure 3 The schematic diagram shows the structure when the contact surfaces are 1, 2, and 3). The advantage of multiple contact surfaces is that the connecting ring 2 is balanced when force is applied, and there is no bending moment. There are several helical surfaces on the same end face, and the helical surfaces have the same rise angle α, which ensures that the rotation angles and support angles of the multiple helical surfaces are synchronized and the force is uniform. If only one helical surface is set on the same end face, after the rotating wedge ring 1 rotates one circle, the distance moved by the connecting ring 1 21 is the helical surface height difference a, and the distance moved by the connecting ring 2 22 is the helical surface height difference b. The adjustable distance range of this mechanism is [0, a+b). To ensure that the end face of the rotating wedge ring 1 is always in contact with the end face of the connecting ring 2, the adjustment distance cannot reach a+b. a and b are arbitrary values, which can be the same or different, and at least one of them is not 0.

[0036] It is explained here that the spiral directions of the spiral surfaces on the same end face are consistent, and refer to the attached diagram, and they all rotate clockwise or counterclockwise; if both connecting rings 2 are provided with spiral surfaces, then the spiral directions of the spiral surfaces of the two connecting rings 2 are opposite. It can be seen from the attached diagram that if the spiral directions are consistent, the wedge ring cannot rotate.

[0037] Combined with Figure 5 Take three-segment helicoid as an example. If one end is unfolded into a plane, it is a right triangle. Then the helicoid number n and the helicoid angle are α, the helicoid median diameter d (refers to the diameter at the center of the helicoid, attached Figure 5 In the figure, r is the radius of the midline of the helicoid, the length of the arc of the midline of the helicoid is πd / n), and the height difference a of the helicoid has the following relationship:

[0038]

[0039] Moreover, when the lift angle α is smaller than the friction angle, the mechanism can achieve self-locking, that is, when the applied torque is removed, the adjusted distance can be maintained by self-locking, and at this time the two connecting rings 2 remain stationary.

[0040] At least one torque application position is set on the rotating wedge ring 1, and it can also be divided into multiple positions. For example, the distance adjustment process requires a small torque, and the force application process requires a large torque. Therefore, a small torque application position and a large torque application position can be set separately. Different torque application positions can be set according to rotation accuracy, speed, etc. It is also possible to set only one place, which is shared by distance adjustment and force application. The form of torque application can be arbitrary, such as gears 31, pulleys, sprockets, wrench grooves or direct drive, etc. As shown in the accompanying drawings, two are set in this example. A groove 32 for applying torque is provided on the circumferential outer wall of the rotating wedge ring 1 for small torque rotation, and a gear 31 is provided on its circumferential outer wall for large torque.

[0041] During operation, there is relative rotation between the rotating wedge ring 1 and the connecting ring 2. In order to reduce the friction between the contact surfaces of the two, a copper slide plate 4 is added between the connecting ring 2 and the rotating wedge ring 1 to reduce the influence of friction, thereby facilitating precise control of the rotation torque and rotation angle. Advantages of this embodiment:

[0042] 1. The distance between the two connecting rings can be adjusted by rotating the wedge ring. The distance can remain unchanged under load through self-locking or holding torque. The structure is simple and stable.

[0043] 2. The rotation angle corresponds accurately to the distance change, and high-precision position change can be achieved by controlling the rotation accuracy;

[0044] 3. The lead angle of the helical surface has a force-increasing effect, so a small torque can also achieve a large force-increasing effect.

[0045] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A force-adding mechanism with adjustable length, characterized in that: It comprises a rotating wedge ring (1) and two connecting rings (2), wherein the two connecting rings (2) are respectively rotatably sleeved on the axial ends of the rotating wedge ring (1), and the three are coaxial. At least one of the upper and lower end faces of the rotating wedge ring (1) is provided with at least one spiral surface. The two connecting rings (2) are connected to an external mechanism and approach each other under the action of an external force. The end face of the rotating wedge ring (1) matches and contacts the end face of the connecting ring (2). Applying torque to rotate the rotating wedge ring (1) will cause the two connecting rings (2) to gradually move away from each other in the axial direction, and the end surface of the rotating wedge ring (1) is always at least partially in contact with the end surface of the connecting ring (2).

2. The length-adjustable force-adding mechanism according to claim 1, characterized in that: The radial section of the spiral surface is a straight line segment, an oblique line segment, a curved line segment, a broken line segment, and an arc segment.

3. The length-adjustable force-adding mechanism according to claim 1, characterized in that: There are several helical surfaces located on the same end face, and the lead angles α of the helical surfaces are consistent.

4. The length-adjustable force-adding mechanism according to claim 3, characterized in that: The number of helical faces on the same end face, n, the helical face pitch angle α, the helical face mid-diameter d, and the helical face height difference a have the following relationship: Furthermore, when the lift angle α is smaller than the friction angle, the two connecting rings (2) will be in a self-locking state.

5. The length-adjustable force-adding mechanism according to claim 1, characterized in that: A copper slide plate (4) for reducing friction is provided between the end surface of the rotating wedge ring (1) and the end surface of the connecting ring (2).

6. The length-adjustable force-adding mechanism according to claim 1, characterized in that: The circumferential outer wall of the rotating wedge ring (1) is provided with a groove (32) and a protrusion for applying torque.

7. The length-adjustable force-applying mechanism according to claim 1, characterized in that: A gear (31) and a pulley are provided on the circumferential outer wall of the rotating wedge ring (1).

Images