CN113531083B

CN113531083B - Flexible space cam mechanism

Info

Publication number: CN113531083B
Application number: CN202110849476.2A
Authority: CN
Inventors: 马俊峰; 王骏; 陆忠华; 朱星宇
Original assignee: Wuxi Institute of Technology
Current assignee: Wuxi Institute of Technology
Priority date: 2021-07-27
Filing date: 2021-07-27
Publication date: 2022-11-01
Anticipated expiration: 2041-07-27
Also published as: CN113531083A

Abstract

The invention discloses a flexible space cam mechanism, which comprises a cam body, a needle roller unit and needle rollers, wherein the cam body is provided with a cam groove; the cam body is a circular mounting frame, a plurality of uniformly distributed mounting grooves are formed in the upper surface of the cam body along the circumferential direction, and a needle roller unit adjustable in depth position along the mounting grooves is arranged in each mounting groove; the top of the needle roller unit is provided with a rotatable needle roller. The invention adopts a plurality of needle roller units with needle rollers at the ends to form a space cam profile, and changes the space profile of the cam by changing the relative positions of the needle roller units, thereby overcoming the defect that the traditional cam profile can not be changed. The roller pins at the tops of the roller pin units have enough bearing capacity, and the roller pin structure is adopted, so that the friction force is greatly reduced, and the friction force of a contact surface of the driven piece and the cam profile is reduced.

Description

Flexible space cam mechanism

Technical Field

The invention belongs to the field of cam mechanisms, and particularly relates to a flexible space cam mechanism.

Background

The cam mechanism is a high-pair mechanism which enables the driven member to move in an expected rule, is generally used in places with strict requirements on the motion rule of the driven member or places where the driven member moves intermittently, and can enable the driven member to move according to the planned rule as long as a corresponding cam profile is designed.

However, the conventional cam mechanism has the following two disadvantages:

1. once the profile of the cam is machined, the profile cannot be adjusted, so that the motion track of the driven piece is fixed, and the motion track of the driven piece cannot be modified.

2. The contact between the follower and the cam contour surface is difficult to ensure good lubrication, and the specific pressure is large, so that the wear is easy, and the transmission power cannot be excessively large to maintain the required service life.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of the prior art and provide a flexible space cam mechanism, which solves the problems that the profile of the traditional space cam cannot be changed, the friction force of the profile contact surface is too large and the bearing capacity is small.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

a flexible space cam mechanism comprises a cam body, a needle roller unit and needle rollers;

the cam body is a circular mounting frame, a plurality of uniformly distributed mounting grooves are formed in the upper surface of the cam body along the circumferential direction, and a needle roller unit adjustable along the depth direction of the mounting groove is arranged in each mounting groove; the top of the needle roller unit is provided with a rotatable needle roller.

Further, the needle roller unit is driven by the needle roller unit lifting driving mechanism to move along the installation groove.

Further, the needle roller unit lifting driving mechanisms are arranged in the corresponding mounting grooves.

Further, scales are arranged on the peripheral side wall of the cam body.

Furthermore, the needle roller unit comprises a support frame arranged on the needle roller unit lifting drive mechanism.

Further, the needle roller is rotatably mounted on the top of the support frame.

Further, each needle roller is arranged along the radial direction of the cam body and rotates around the axis of the needle roller.

Further, each of the needles forms an adjustable cam profile above the cam body.

Furthermore, the roller pins are conical roller pins.

Furthermore, the needle roller unit lifting driving mechanism comprises a lower mounting seat, an upper mounting seat and four symmetrical support rods, wherein the shear forks are hinged between the lower mounting seat and the upper mounting seat; one ends of the four support rods are hinged in pairs, and the other ends of the four support rods are hinged on the lower mounting seat and the upper mounting seat in pairs respectively; a movably-through adjusting bolt is arranged at the hinged point of the four support rods; one end of the adjusting bolt is in threaded connection with a locking nut.

The invention achieves the following beneficial effects:

aiming at the defects that the traditional cam profile cannot be changed, the friction force between the driven piece and the surface of the cam profile is large and the bearing capacity is small, the invention adopts a plurality of needle roller units with needle rollers at the ends to form a space cam profile, and changes the space profile of the cam by changing the relative positions of the needle roller units, thereby overcoming the defect that the traditional cam profile cannot be changed. The roller pins at the tops of the roller pin units have enough bearing capacity, and the roller pin structure is adopted, so that the friction force is greatly reduced, and the friction force of a contact surface of the driven piece and the cam profile is reduced.

Drawings

Fig. 1 is a schematic view of the flexible space cam mechanism of the present embodiment.

Fig. 2 is a schematic view of the flexible space cam mechanism in which a needle roller unit is separated.

Fig. 3 is an assembly view of the needle roller unit elevation drive mechanism, the needle roller unit, and the needle rollers in fig. 1.

Fig. 4 is a schematic view of the needle roller unit elevation driving mechanism in fig. 3.

In the figure, the position of the first and second end faces,

wherein: 1. a cam body; 11. mounting grooves; 12. calibration; 2. a needle roller unit lifting driving mechanism; 21. a lower mounting seat; 22. an upper mounting seat; 23. a stay bar; 24. adjusting the bolt; 25. locking the nut; 3. a needle roller unit; 4. rolling needles; 5. a driven member.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

As shown in fig. 1, 2, 3 and 4, the flexible space cam mechanism in the present embodiment includes a cam body 1, a needle unit elevation drive mechanism 2, a needle unit 3 and needles 4.

The cam body 1 is a circular ring body mounting frame, and a plurality of uniformly distributed mounting grooves 11 are formed in the upper surface of the cam body along the circumferential direction. A needle roller unit 3 capable of adjusting the vertical position is respectively arranged in each mounting groove 11 on the cam body 1. Each needle unit 3 is driven by a corresponding needle unit elevation driving mechanism 3 to move up and down along the mounting groove 11, and each needle unit elevation driving mechanism 2 is also disposed in each corresponding mounting groove 11. The cam body 1 is provided on the outer peripheral side wall thereof with a scale 12, and the scale 12 is used to indicate the vertical height of the needle roller unit 3 so as to adjust the needle roller unit 3 to a proper position.

One end of the mounting groove 11 facing the center of the cam body 1 is smaller in size than the other end facing the outer periphery of the cam body 1.

The needle roller unit 3 includes a support frame provided on the needle roller unit elevation drive mechanism 2. The support bracket is matched with the mounting groove 11 in shape, and one end of the support bracket facing the center of the cam body 1 is smaller than the other end facing the periphery of the cam body 1, so that the support bracket can be accommodated in the mounting groove 11 in a more matched manner.

The top of the supporting frame is provided with a rotatable roller pin 4. The needle rollers 4 are arranged along the radial direction of the cam body 1 and rotate around the axes of the needle rollers to form a cam profile surface which can adjust the motion trail of the driven member 5 in the circumferential direction, so that the spatial cam profile surface has flexibility, when the motion trail of the driven member 5 needs to be changed, a cam does not need to be manufactured additionally, and the corresponding positions of the needle roller units 3 can be directly adjusted by driving of the needle roller unit lifting driving mechanisms 2.

In this embodiment, the needle rollers 4 are conical needle rollers.

The needle roller unit lifting driving mechanism 2 comprises a lower mounting seat 21, an upper mounting seat 22 and four supporting rods 23, wherein the four supporting rods 23 are symmetrically hinged between the lower mounting seat 21 and the upper mounting seat 22 through scissors, one ends of the four supporting rods 23 are hinged in pairs, the other ends of the four supporting rods 23 are hinged on the lower mounting seat 21 and the upper mounting seat 22 in pairs, and the height distance between the lower mounting seat 21 and the upper mounting seat 22 is adjusted by adjusting the four supporting rods 23. The needle roller unit 3 is mounted on the upper mount 22 to move together with the upper mount 22. An adjusting bolt 24 can penetrate through the hinged point of the four support rods 23, when the adjusting bolt 24 is inserted into the hinged point, the four support rods 23 cannot realize adjusting movement, and the height distance between the lower mounting seat 21 and the upper mounting seat 22 is fixed. One end of the adjusting bolt 24 is threadedly coupled with a locking nut 25 for locking the adjusting bolt 24.

When the space cam profile surface trajectory adjusting device works, firstly, according to the requirement of the motion trajectory of the driven part 5, the needle roller units 3 corresponding to the highest point, the lowest point and the trajectory inflection point of the trajectory on the space cam are found by using the scales 12 on the peripheral side wall of the cam body 1, the upper and lower positions of the needle roller units 3 are moved by combining a mechanical structure through adjusting the adjusting bolt 24 to be matched with the motion trajectory of the driven part 5, then, the upper and lower positions of the rest needle roller units 3 are adjusted by combining the motion trajectory ascent angle of the driven part 5 to be matched with the trajectory, and finally, the locking nuts 25 on the adjusting bolt are screwed, so that the space cam profile surface trajectory adjustment is completed.

The invention overcomes the defect that the profile of the traditional cam cannot be changed, increases the bearing capacity of the cam, and reduces the friction force of the contact surface of the driven piece and the cam profile.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. A flexible space cam mechanism is characterized in that: comprises a cam body (1), a needle roller unit lifting driving mechanism (2), a needle roller unit (3) and a needle roller (4);

the cam body (1) is a circular mounting frame, a plurality of uniformly distributed mounting grooves (11) are formed in the upper surface of the cam body along the circumferential direction, and a needle roller unit (3) adjustable along the depth direction of the mounting grooves (11) is arranged in each mounting groove (11); the top of the needle roller unit (3) is provided with a rotatable needle roller (4);

each needle roller unit (3) is driven by a corresponding needle roller unit lifting driving mechanism (2) to move along the mounting groove (11);

each needle roller unit lifting driving mechanism (2) is arranged in the corresponding mounting groove (11);

the needle roller unit lifting driving mechanism (2) comprises a lower mounting seat (21), an upper mounting seat (22) and four symmetrical support rods (23) with scissors hinged between the lower mounting seat (21) and the upper mounting seat (22); one ends of the four support rods (23) are hinged in pairs, and the other ends of the four support rods (23) are hinged on the lower mounting seat (21) and the upper mounting seat (22) in pairs respectively; a movably penetrating adjusting bolt (24) is arranged at the hinge point of the four support rods (23); one end of the adjusting bolt (24) is connected with a locking nut (25) in a threaded manner.

2. A flexible space cam mechanism according to claim 1, wherein: scales (12) are arranged on the peripheral side wall of the cam body (1).

3. A flexible space cam mechanism according to claim 1, wherein: the needle roller unit (3) comprises a support frame arranged on the needle roller unit lifting driving mechanism (2).

4. A flexible space cam mechanism according to claim 3, wherein: the needle roller (4) is rotatably arranged on the top of the support frame.

5. A flexible space cam mechanism according to claim 1 or 4, wherein: the needle rollers (4) are arranged along the radial direction of the cam body (1) and rotate around the axes of the needle rollers.

6. A flexible space cam mechanism according to claim 1, wherein: each needle roller (4) forms an adjustable cam profile surface above the cam body (1).

7. A flexible space cam mechanism according to claim 1, wherein: the roller pins (4) are conical roller pins.