阅读说明：本技术 不可调的摩擦式差速器变矩扳手 (Nonadjustable friction type differential mechanism torque-changing wrench ) 是由 汪学品 于 2020-04-19 设计创作，主要内容包括：不可调的摩擦式差速器变矩扳手,包括差速组件、摩擦组件、施力杆和输出头,所述差速组件包括行星轮、主动轮、从动轮和差速壳体,所述行星轮支承于所述行星齿轮轴上,所述行星齿轮轴支承于所述差速壳体上,所述主动轮和所述从动轮直接支撑于所述差速壳体上,并且都与所述行星轮啮合；所述摩擦组件包括摩擦鼓、摩擦片,所述摩擦鼓与所述主动轮连接,两者之间不能相对运动；所述摩擦片的一端支承于所述差速壳体,所述摩擦片在自由状态下的内径比所述摩擦鼓的直径稍大。(The nonadjustable friction type differential mechanism torque conversion wrench comprises a differential assembly, a friction assembly, a force application rod and an output head, wherein the differential assembly comprises planet wheels, a driving wheel, a driven wheel and a differential shell, the planet wheels are supported on planet wheel shafts, the planet wheel shafts are supported on the differential shell, and the driving wheel and the driven wheel are directly supported on the differential shell and are meshed with the planet wheels; the friction assembly comprises a friction drum and a friction plate, the friction drum is connected with the driving wheel, and the friction drum and the driving wheel cannot move relatively; one end of the friction plate is supported on the differential shell, and the inner diameter of the friction plate in a free state is slightly larger than the diameter of the friction drum.)

1. Nonadjustable friction formula differential mechanism torque conversion spanner, its characterized in that: the differential assembly comprises planet wheels, a driving wheel, a driven wheel and a differential shell, wherein the planet wheels are supported on planet wheel shafts, the planet wheel shafts are supported on the differential shell, and the driving wheel and the driven wheel are directly supported on the differential shell and are meshed with the planet wheels;

the friction assembly comprises a friction drum and a friction plate, the friction drum is connected with the driving wheel, and the friction drum and the driving wheel cannot move relatively;

one end of the friction plate is supported on the differential shell, and the inner diameter of the friction plate in a free state is slightly larger than the diameter of the friction drum;

the force application rod comprises a force arm, a rotating hole, a friction ring and a handle, wherein the friction ring is a circular ring, and the inner diameter of the circular ring is slightly larger than the diameter of a circle formed by the friction plates in a free state; the force arm and the handle are fixedly connected to the circumferential surfaces of the two sides of the friction ring respectively, and a rotating hole is formed in the force arm;

the differential shell is provided with a stress rod and a rotating shaft, and the rotating shaft can extend into the rotating hole;

one end of the friction plate is fixedly connected with a supporting shaft, a supporting hole is formed in the shell, and the supporting shaft is inserted into the supporting hole in a clearance fit mode, so that the friction plate can rotate around the supporting shaft.

2. The non-adjustable friction differential torque converter wrench of claim 1, wherein: the force application rod can apply pressure to the friction plate so as to enable the friction plate to be pressed on the friction drum, and the force application rod is further connected with the differential shell.

3. The non-adjustable friction differential torque converter wrench of claim 1, wherein: the output head is fixedly connected with the driven wheel.

4. The non-adjustable friction differential torque converter wrench of claim 1, wherein: the output head is a square column.

5. The non-adjustable friction differential torque converter wrench of claim 1, wherein: the differential shell is of a frame-shaped structure integrally cast.

Technical Field

The invention relates to a torque-converting wrench, in particular to an unadjustable friction type differential mechanism torque-converting wrench.

Background

The wrench is one of the essential tools in life and production of people, can be used by teaching in schools, and mainly utilizes the wrench to learn some knowledge and skills. In operation, the wrench screws the nut or bolt, thereby tightening the object. However, after the nut or the bolt is tightened as specified, elastic deformation and plastic deformation occur, so that the nut and the bolt are used as required for a specified number of times, and the strength of the nut and the bolt cannot meet the requirement if the number of times exceeds the limit of the number of times. In actual use, the number of times of use is generally not exceeded, but in teaching, the use of nuts and bolts according to the required number of times is difficult to realize. Each class has dozens of students, each student can have dozens of times after training, in order to strengthen the training effect, some students still can train more than once, in addition to the use during examination, in this way, one class can use the nut or the bolt hundreds of times. If each student is equipped with a new nut or bolt, it will be a significant expense. Some bolts or nuts are integrated with parts, and if the bolts or nuts are damaged, the parts need to be replaced, which brings great burden to teaching cost.

The current method for solving the problem is mainly to screw the nut or bolt according to a specified torque, for example, the torque required in practical use is 100NM, and only 60NM is required in teaching, so that the loss of the nut or the bolt can be avoided. However, the disadvantage of this is that the student does not have a very intuitive force application feeling, and the student feels that the force application feeling is very similar to playing and lacks the immersion feeling of learning; secondly, the bad habit of irregular operation is easily developed for the trainees.

Therefore, there is a need for a wrench that provides an intuitive force application feeling to a student without damaging the nut or bolt.

Disclosure of Invention

In order to solve the technical problem, the invention provides an unadjustable friction type differential torque-converting wrench.

The nonadjustable friction type differential mechanism torque conversion wrench comprises a differential assembly, a friction assembly, a force application rod and an output head, wherein the differential assembly comprises planet wheels, a driving wheel, a driven wheel and a differential shell, the planet wheels are supported on planet wheel shafts, the planet wheel shafts are supported on the differential shell, and the driving wheel and the driven wheel are directly supported on the differential shell and are meshed with the planet wheels;

the friction assembly comprises a friction drum and a friction plate, the friction drum is connected with the driving wheel, and the friction drum and the driving wheel cannot move relatively; one end of the friction plate is supported on the differential shell, and the inner diameter of the friction plate in a free state is slightly larger than the diameter of the friction drum;

the force application rod comprises a force arm, a rotating hole, a friction ring and a handle, wherein the friction ring is a circular ring, and the inner diameter of the circular ring is slightly larger than the diameter of a circle formed by the friction plates in a free state; the force arm and the handle are fixedly connected to the circumferential surfaces of the two sides of the friction ring respectively, and a rotating hole is formed in the force arm;

the differential shell is provided with a stress rod and a rotating shaft, and the rotating shaft can extend into the rotating hole.

Preferably, one end of the friction plate is fixedly connected with a support shaft, and the housing is provided with a support hole, and the support shaft is inserted into the support hole in a clearance fit manner, so that the friction plate can rotate around the support shaft.

The force application rod can apply pressure to the friction plate so as to press the friction plate to the friction drum, and the force application rod is also connected with the differential shell;

the output head is fixedly connected with the driven wheel.

Preferably, the force application rod comprises an adjusting arm, an adjusting hole, a friction ring and a handle, wherein the friction ring is a circular ring, and the inner diameter of the circular ring is slightly larger than the diameter of a circle formed by the friction plates in a free state; the adjusting arm and the handle are fixedly connected to the circumferential surfaces of the two sides of the friction ring respectively, and the adjusting arm is provided with an adjusting hole.

Preferably, the differential housing is provided with an adjusting rod and an adjusting shaft capable of moving on the adjusting rod, and the adjusting shaft can extend into the adjusting hole.

Preferably, the output head is a square column.

Preferably, the differential housing is a unitary cast frame structure.

Drawings

Fig. 1 is a partially exploded schematic view of the present invention.

FIG. 2 is a force analysis diagram of the friction drum of the present invention.

Fig. 3 is a force analysis of the force application rod.

In the figure: 1-handle, 2-friction drum, 3-friction plate, 4-friction ring, 5-force arm, 6-rotation hole, 7-rotation shaft, 8-stress rod, 9-differential shell, 10-connecting block, 11-driving wheel, 12-planetary wheel, 13-driven wheel, 14-output head, 15-supporting hole, 16-supporting shaft and 18-friction plate shaft hole.

Detailed Description

In order to more clearly explain the detailed structure and principle of the present invention, the following further describes the embodiments of the present invention with reference to the attached drawings.

As shown in fig. 1, the present invention comprises a differential assembly, a friction assembly, a force application rod and an output head, wherein the differential assembly comprises a differential housing, two planetary gears supported on the differential housing, a driving wheel engaged with the two planetary gears simultaneously and a driven wheel engaged with the two planetary gears simultaneously; the friction assembly comprises a friction drum fixedly connected with the driving wheel and a friction plate capable of being pressed and separated with the friction drum; the force application rod comprises a force application circle which can apply pressure to the friction plate; the handle is fixedly connected with the force application circle, and the adjusting arm is fixedly connected with the force application circle; the output head is fixedly connected with the driven wheel. In the above structure, the friction plate is a partial ring structure, and is supported in a support hole provided in the differential belt housing by a support shaft fixedly connected to one end thereof, so that the friction plate can rotate around the support shaft. The difference between the outer diameter of the friction drum and the inner diameter of the force application circle is larger than the difference between the diameters of the two circles of the circular ring of the friction plate, so that the friction plate has enough rotating space.

The working principle of the present invention is described below.

For the differential assembly, when the differential shell rotates integrally around the axis of the driving wheel, the planetary gear supported on the differential shell is driven to rotate, namely the revolution of the planetary gear; then, the planet gear drives the driving wheel and the driven wheel which are meshed with the planet gear to rotate. When the resisting moments of the driving wheel and the driven wheel are the same, the driving wheel, the driven wheel and the planetary gear do not rotate relatively, and the planetary gear only revolves; if the resistance moments of the driving wheel and the driven wheel are different, the planetary gear revolves and also rotates, and the driving wheel, the driven wheel and the planetary gear rotate relatively. When no other external force is introduced, the side with large resisting torque stops rotating, and the side with small resisting torque rotates at the speed 2 times that of the differential shell. Therefore, the driving wheel and the driven wheel must be subjected to the same resisting torque to keep the balance of the system.

In this application, because action wheel and friction drum are the rigid coupling together, so the moment of resistance that the action wheel received is exactly the moment of resistance that the friction drum received.

And (5) carrying out stress analysis on the force application rod. As shown in fig. 2, assume that the distance between the friction ring and the force F is a and the distance between the friction ring and the adjustment axis is b. When the vertical acting force is applied to the handle of the force application rod during operation, the vertical acting force is F1, the reaction force of the adjusting shaft to the force application rod is F2, and the reaction force of the friction drum to the friction ring is F3, so that the directions of F3 are opposite to those of F1 and F2, and the magnitude of the F3 satisfies F3= F1+ F2. For the F2 point, the moments are balanced, with F1 = F3= F1 = F1 = (a + b)/b, thus there is F3= F1 = F3 × (a + b)/b.

From the principle of force and reaction, F3 is also the pressure exerted by the friction ring on the friction plate. Then, the force of the friction drum is analyzed.

As shown in fig. 3, assuming that the radius of the friction drum is R, the friction system between the friction drum and the friction plate is u, and the equivalent positive pressure of the friction plate on the friction drum is N, N and F3 are necessarily in a corresponding relationship, assuming that N = c × F3, c is a constant, and the torque applied to the friction drum is M1, there are: m1= u × N × R = u × c × F3 × R. As can be seen from the above analysis, the friction drum and the driving wheel are connected into a whole, and the torque applied to the driving wheel and the torque applied to the driven wheel are the same, i.e., the torque applied to the driven wheel is only M, otherwise, either the driving wheel rotates at a speed 2 times that of the differential housing and the driven wheel does not rotate, or the driven wheel rotates at a speed 2 times that of the differential housing and the driving wheel does not rotate.

For the operator, who applies the force F1, the resulting effect is a rotation of the differential housing, with a rotational arm of force a, and the moment M2= F1 a, which is also the intuitive perceived moment obtained by the operator.

In summary, M1= u × N × R = u × c F3 × R, M2= F1 × a, F3= F1 (a + b)/b, it can be found that: M2/M1= (a × b)/u × c × R = (a + b). Where c and R are both constants, and u is also a fixed value for a given drum and plate. Thus, the ratio of M1 to M2 can be adjusted by simply determining the values of a and b in advance, i.e., the operator's perceived torque is not the same as the actual torque acting on the driven wheel. It is also possible to determine u in advance to achieve that the sensed torque of the operator is different from the torque actually acting on the driven wheels.

The invention has no planet gear shaft, simplifies the structure and reduces the cost.