CN111288094B

CN111288094B - Electronic clutch and release system thereof

Info

Publication number: CN111288094B
Application number: CN201811495702.6A
Authority: CN
Inventors: 何小明; 姜超; 李益南
Original assignee: SAIC Motor Corp Ltd
Current assignee: SAIC Motor Corp Ltd
Priority date: 2018-12-07
Filing date: 2018-12-07
Publication date: 2021-05-25
Anticipated expiration: 2038-12-07
Also published as: CN111288094A

Abstract

The invention provides an electronic clutch and a separating system thereof, which have high transmission efficiency and compact structure. The device comprises a separating cylinder and a lead screw pair, wherein a nut sleeve of the lead screw pair is fixedly connected with a piston rod of the separating cylinder, and a lead screw of the lead screw pair is connected with a power source for driving the lead screw pair to rotate; the power source drives the screw rod to rotate so as to drive the nut sleeve to move axially along the screw rod, and further the piston rod is pushed to perform a separation action; the nut sleeve is connected with an elastic piece in a pre-compression state, and when the nut sleeve pushes the piston rod to perform separation action, the elastic piece provides an auxiliary pushing force; one end of the nut sleeve is provided with a reverse spiral line so as to form self-locking with the screw rod at the final stage of separation and maintain the electronic clutch in a normally open state. The screw pair has high transmission efficiency and precision and small volume; and the elastic piece can play the helping hand effect in the screw sleeve axial motion process, further reduces the power requirement to the power supply.

Description

Electronic clutch and release system thereof

Technical Field

The invention relates to the technical field of clutch systems, in particular to an electronic clutch and a separating system thereof.

Background

In the prior art, a motor of a clutch is connected with a worm gear, the worm gear is connected with a piston rod of a main cylinder through a transmission rod, and the transmission rod is driven to swing in the rotation process of the worm gear so as to drive the piston rod to reciprocate; the rodless cavity of the main cylinder is communicated with the clutch oil cylinder, and when a piston rod of the main cylinder reciprocates, the pressure of the rodless cavity of the main cylinder can be changed, so that the pressure of the clutch oil cylinder is changed, and the separation and combination actions are completed.

Because the separation curve of the clutch is hill-shaped, namely, the power required by the clutch is smaller in the early separation period, and the power required by the clutch is larger in the later separation period, the output power of the motor is excessive in the early separation period of the clutch and energy waste exists for the motor with fixed power, and the output power of the motor is too small in the later separation period of the clutch and is not enough to drive the clutch to complete the separation action.

In order to solve the technical problem, a power spring is arranged in the prior art and is connected with a transmission rod connected to a worm wheel, so that excessive energy is stored in the early stage of separation of the clutch and is supplied to the later stage of separation for use, and the power spring plays a role in assisting power in the later stage of separation of the clutch.

However, the clutch release system has a large structure and requires a large installation space due to the adoption of the worm gear and the power spring; particularly, the transmission efficiency of the worm gear is low, the corresponding speed of the separating action is reduced, and the reliability and the stability of the separating action are influenced.

Therefore, it is desirable to design an electronic clutch and a release system thereof to improve the transmission efficiency and make the structure of the release system more compact.

Disclosure of Invention

The invention aims to provide an electronic clutch and a separating system thereof, which have high transmission efficiency and compact structure.

In order to achieve the purpose, the invention provides a separation system of an electronic clutch, which comprises a separation cylinder and a lead screw pair, wherein a nut sleeve of the lead screw pair is fixedly connected with a piston rod of the separation cylinder, and a lead screw of the lead screw pair is connected with a power source for driving the lead screw pair to rotate; the power source drives the screw rod to rotate so as to drive the nut sleeve to move axially along the screw rod, and further the piston rod is pushed to perform a separation action; the nut sleeve is connected with an elastic piece in a pre-compression state, and when the nut sleeve pushes the piston rod to perform separation action, the elastic piece provides an auxiliary pushing force; one end of the nut sleeve is provided with a reverse spiral line so as to form self-locking with the screw rod at the final stage of separation and maintain the electronic clutch in a normally open state.

According to the separating system, the piston rod of the separating cylinder is driven to act by the lead screw pair, and compared with a worm gear in the prior art, the lead screw pair is high in transmission efficiency, loss of power in a transmission process can be reduced, and therefore a motor with low power can be selected as a power source; compared with a worm gear, the screw pair is small in size and high in transmission precision; particularly, the nut sleeve of the screw pair is also connected with an elastic part, the elastic part can play a role of assisting in the axial movement process of the nut sleeve, the power requirement on a power source is further reduced, and a low-power motor can be selected to complete the separation action; when selecting for use the miniwatt motor as the power supply, just reduced the volume of power supply, the integrated setting of lead screw pair and elastic component for the piece-rate system of this scheme has more compact structure, satisfies the user demand under the restricted condition of installation space better.

More importantly, the end part of the screw sleeve is provided with the reverse spiral line for realizing self-locking of the screw rod, the mechanical self-locking mode is high in reliability, a power source is not needed to provide self-locking force, the structure is simplified, energy is saved, and the self-locking requirement of the electronic clutch in a normally open state can be better met.

Optionally, the screw assembly is a ball screw assembly, the ball screw assembly adopts a variable lead helix, and the lead in the low separating force area is large and the lead in the high separating force area is small.

Optionally, the power source is a motor, and an output shaft of the motor is connected with an input end of the screw rod through a reduction gear set.

Optionally, the reduction gear set is a planetary gear set, and includes a sun gear sleeved on the output shaft and at least one stage of planet gear meshed with the sun gear, and the planet gear at the final stage is fixedly connected with the input end of the screw rod.

Optionally, the reduction gear set is provided with at least two final planetary gears, and the planetary gears of each final stage are fixedly connected to the input end of the screw rod at intervals in the circumferential direction.

Optionally, the input end of the screw rod is fixedly connected with a first flange, the nut sleeve is fixedly connected with a second flange arranged opposite to the first flange, and the elastic element is axially pre-compressed between the first flange and the second flange.

Optionally, the elastic element is a pressing sheet type spring sleeved outside the nut sleeve; the sleeve of the nut sleeve extends in the axial direction of the screw rod to support the elastic piece.

Optionally, the nut cover is one end open-ended tube-shape, the open end of nut cover will inside the lead screw cover, the blind end is equipped with the connector, the piston rod have with the connecting hole of connector fixed fit.

Optionally, the hydraulic motor further comprises a housing having a hollow cavity, and two ends of the housing are respectively connected with the separation cylinder and the motor, so that the reduction gear set, the screw rod, the nut sleeve and part of the separation cylinder are enclosed in the hollow cavity of the housing.

The invention also provides an electronic clutch which comprises the separation system.

Drawings

FIG. 1 is a schematic perspective view of an electronic clutch provided herein in one embodiment;

FIG. 2 is a schematic front view of the electronic clutch shown in FIG. 1;

FIG. 3 is a schematic cross-sectional view of the electronic clutch shown in FIG. 1;

FIG. 4 is a schematic diagram of a lead screw of the electronic clutch of FIG. 1 in one arrangement;

FIG. 5 is a schematic diagram showing the relationship between the separation stroke and the separation force using the lead screw shown in FIG. 4;

FIG. 6 is a schematic diagram of a nut sleeve of the electronic clutch of FIG. 1 in one arrangement;

fig. 7 is a schematic view of force analysis of the lead screw when the nut sleeve shown in fig. 1 is adopted.

In fig. 1-7:

the device comprises a separation cylinder-1, a piston rod-11, a nut sleeve-2, a second flange-21, a sleeve-22, a connector-23, a forward spiral line-24, a reverse spiral line-25, a screw rod-3, a first flange-31, a power source-4, an output shaft-41, an elastic part-5, a reduction gear set-6, a sun gear-61, a planet gear-62, a shell-7 and a hollow cavity-71.

Detailed Description

The following description of the present invention will be provided in order to enable those skilled in the art to more accurately understand the technical solutions of the present invention.

The scheme relates to a separation system of an electronic clutch, which is a system for realizing the separation action of the clutch in the electronic clutch, and the system specifically comprises a separation cylinder 1, a clutch oil cylinder and a component for executing separation, wherein the separation cylinder 1 is communicated with the clutch oil cylinder, is equivalent to a pilot oil cylinder of the clutch oil cylinder and is used for changing the working condition of the clutch oil cylinder and further controlling the component for executing separation to act so as to complete the separation of the clutch.

The separating system of the invention mainly relates to the improvement of a driving and controlling component for controlling the separating cylinder 1.

As shown in fig. 1-3, the separation system includes a screw pair, the screw pair includes a screw rod 3 and a nut sleeve 2, the screw rod 3 is connected with a power source 4, the screw rod 3 rotates around its own axis under the driving of the power source 4, the nut sleeve 2 is connected with a piston rod 11 of the separation cylinder 1, and the circumferential rotation of the nut sleeve 2 is limited, when the screw rod 3 rotates, the nut sleeve 2 is driven to move axially along the screw rod 3, so as to drive the piston rod 11 to move axially to perform the separation action.

The separating operation is a continuous operation here, and means an operation of each member directly or indirectly connected to the piston rod 11 of the separating cylinder 1. Specifically, the rodless cavity of the release cylinder 1 is communicated with the clutch cylinder, and when the piston rod 11 moves axially to compress the rodless cavity of the release cylinder 1, the pressure of the rodless cavity is increased, and then the rodless cavity acts on the clutch cylinder, so that the clutch cylinder drives the direct execution component connected with the clutch cylinder to act, and then the release of the clutch is completed. That is, the release operation performed by the piston rod 11 of the release cylinder 1 actually includes a compression operation in which the piston rod 11 compresses the non-piston rod 11, a pressure transmission operation in which the release cylinder 1 transmits a pressure change caused by the compression operation to the clutch cylinder, a control operation of the direct actuator by the clutch cylinder, and a release execution operation of the direct actuator.

And, the nut sleeve 2 is still connected with the elastic component 5, this elastic component 5 is in the precompression state, when the nut sleeve 2 moves along the axial of the lead screw 3 and pushes the piston rod 11 to carry out the separation action, the elastic component 5 provides the auxiliary driving force, namely this elastic component 5 has the effort the same as the direction of motion of the nut sleeve 2, so that in the process that the nut sleeve 2 moves along the axial of the lead screw 3, the auxiliary driving nut sleeve 2, finally act on the piston rod 11 through the nut sleeve 2, carry out the separation action to the piston rod 11 and play the helping hand effect.

As such, the nut case 2 actually receives two forces: a force is applied from the rotation of the screw rod 3, the rotation enables the screw sleeve 2 to move spirally relative to the screw rod 3, and the spiral movement is further decomposed into axial movement and circumferential rotation of the screw sleeve 2 relative to the screw rod 3; the other force comes from the elastic deformation of the elastic member 5, and since the elastic member 5 is in the pre-compressed state, there is an elastic force to restore the elastic deformation, which generates a force to push the nut sleeve 2 to move axially along the screw rod 3. Therefore, under the combined action of the two acting forces, the nut sleeve 2 moves axially along the screw rod 3, and further pushes the piston rod 11 to move axially, so that the piston rod 11 moves axially in the cavity of the separation cylinder 1.

Just because the force that nut cover 2 acted on piston rod 11 has two sources, one comes from power supply 4, and one comes from elastic component 5 for elastic component 5 has played the helping hand effect, when adopting the motor as power supply 4, just can select for use the miniwatt motor to accomplish the drive control of separation action. On one hand, the requirement of the power source 4 on the power of the motor is reduced, and the cost can be reduced; on the other hand, the small-power motor has smaller volume, so that the volume can be reduced; more importantly, elastic component 5 is integrated in nut sleeve 2 in fact, and compare with setting alone, this kind of integrated structural style makes the structure of piece-rate system more compact, when realizing integrating, has reduced piece-rate system's overall dimension to a great extent, has reduced piece-rate system to installation space's requirement, can be applied to the multiple environment that installation space is limited.

As described in the background of the invention: the clutch is characterized in that the separation curve of the clutch is of a hill shape, namely, the power required by the clutch is smaller in the early separation period and larger in the later separation period; therefore, for a motor with fixed power, in the early stage of the separation of the clutch, the output power of the motor is excessive, and energy is wasted, and in the later stage of the separation of the clutch, the output power of the motor is too small to drive the clutch to complete the separation action. Therefore, a booster structure is required to be provided so that the power source 4 can employ a low-power motor without affecting the drive control of the clutch release operation. However, in the prior art, such a boosting structure is a separate member disposed outside the power source 4 and the transmission mechanism, which undoubtedly increases the complexity of the structure and also affects the installation space and the like. This application adopts elastic component 5 helping hand to with elastic component 5 integration in nut cover 2, above-mentioned technical problem of solution that can be fine.

In addition, the worm gear and the worm are adopted for transmission in the prior art, so that the transmission efficiency is low, the transmission precision is poor, and the size is huge. Compared with the prior art, the screw pair is adopted, so that the transmission efficiency is improved, the transmission precision is improved, and the size of a transmission part is greatly reduced. Tests show that the transmission efficiency of the worm gear and the worm is about 50%, and the transmission efficiency of the screw pair can reach more than 90%.

As shown in fig. 1, when the power source 4 is a motor, an output shaft 41 of the motor may be connected to an input end of the lead screw 3 through a reduction gear set 6. Specifically, one axial end of the screw rod 3 may be defined as an input end, the input end is connected to the output shaft 41 of the motor through the reduction gear set 6, and the other axial end of the screw rod 3 extends into the nut sleeve 2 and is connected to the nut sleeve 2.

The reduction gear set 6 may be a planetary gear set, and includes a sun gear 61 sleeved on the output shaft 41 of the motor and at least one stage of planetary gear 62 meshed with the sun gear 61, and the final stage of planetary gear 62 is fixedly connected with the input end of the screw rod 3.

The first-stage planetary gear 62 directly meshing with the sun gear 61 may be defined as a first-stage planetary gear 62, the next-stage planetary gear 62 meshing with the first-stage planetary gear 62 is defined as a second-stage planetary gear 62, and so on. In the present application, three-stage planetary gears 62 may be employed, i.e., the final planetary gear 62 is the third-stage planetary gear 62. It will be appreciated that the number of stages of planet gears 62 and the number of planet gears 62 in each stage can be specifically configured to achieve a desired ratio, as desired.

The planetary gear set may be provided with a planet carrier, and the inner ring of the planet carrier may mesh with the second stage planet wheel 62 or the last but one stage planet wheel 62 to prevent the planet wheel 62 from idling, and realize the step-by-step transmission from the sun wheel 61 to each stage planet wheel 62.

As shown in fig. 1, the reduction gear set 6 may be provided with at least two final planetary gears 62, and each final planetary gear 62 is fixedly connected to the input end of the screw rod 3 at intervals in the circumferential direction, so as to improve the driving reliability and stability of the screw rod 3.

The screw pair that this scheme adopted specifically can be ball screw pair, and coefficient of friction is low, is favorable to improving transmission efficiency.

As shown in fig. 2 and 3, the input end of the screw rod 3 is fixedly connected with a first flange 31, the nut sleeve 2 is fixedly connected with a second flange 21 arranged opposite to the first flange 31, and the first flange 31 and the second flange 21 are respectively arranged at two axial ends of the elastic member 5, so that the elastic member 5 is axially pre-compressed between the first flange 31 and the second flange 21. When the nut sleeve 2 moves axially along the screw rod 3, the elastic piece 5 can push the nut sleeve 2 towards the direction of the axial movement of the nut sleeve 2, so as to play a role in assisting power.

When the input end of the screw 3 is fixedly connected with the first flange 31, the planet wheel 62 at the final stage in the reduction gear set 6 can be connected with the first flange 31; when the final stage of the reduction gear set 6 is provided with a plurality of planet wheels 62, the planet wheels 62 at the final stage may be spaced apart circumferentially of the first flange 31 and connected to the axial ends of the first flange 31.

The first and second components described herein are merely for distinguishing between two components of the same or similar structure and do not imply any particular order whatsoever. The flange is a structure protruding from the screw rod 3 or the nut sleeve 2, and is not limited to a disc or the like as long as the elastic member 5 can be axially positioned.

As shown in fig. 3, the elastic member 5 may be a pressing plate type spring sleeved outside the nut sleeve 2; the sleeve 22 of the nut case 2 extends in the axial direction of the lead screw 3 to support the elastic member 5. When the tablet spring is adopted, on one hand, the axial size of the compressed elastic piece 5 can be as small as possible, so that the structural size of the whole separation system is reduced in an auxiliary manner; on the other hand, the tablet spring has larger elastic deformation capacity and can provide larger auxiliary thrust.

The nut sleeve 2 can be in a cylindrical shape with an opening at one end, the sleeve 22 forms a main body of the nut sleeve 2, the screw rod 3 is sleeved in the opening end of the nut sleeve 2, at the moment, the inner wall of the sleeve 22 is in threaded fit with the screw rod 3, and the elastic piece 5 is sleeved outside the sleeve 22 and supported by the sleeve 22. The closed end of the nut sleeve 2 is provided with a connector 23, and the piston rod 11 is provided with a connecting hole fixedly matched with the connector 23 so as to realize the fixed connection of the nut sleeve 2 and the piston rod 11. The connector 23 may specifically extend axially away from the open end of the nut sleeve 2 to extend into the connecting hole of the piston rod 11, and is fixedly connected with the piston rod 11. In order to improve the connection reliability, the connector 23 may be in a gourd shape, or may be provided with a variable diameter as required.

In order to integrate the separating system, the present application further includes a housing 7 having a hollow cavity 71, and both ends of the housing 7 are respectively connected to the separating cylinder 1 and the motor, so as to enclose the reduction gear set 6, the screw rod 3, the nut sleeve 2 and a portion of the separating cylinder 1 in the hollow cavity 71 of the housing 7. The shell 7 can connect the motor and the separating cylinder 1 into a whole, and can form a hollow cavity 71, and the parts of the reduction gear set 6, the screw rod 3, the nut sleeve 2 and the separating rod at one end of the piston rod 11 are all surrounded to form a protective cavity.

As shown in fig. 4 and 5, the screw pair may adopt a variable-lead spiral, and in this case, since the spiral lines of the screw 3 and the nut sleeve 2 are matched with each other, both of them adopt the variable-lead spiral. Fig. 4 shows only the spiral of the spindle 3, but it will be understood by those skilled in the art that the spiral of the nut sleeve 2 can be arranged to match the spindle 3.

As shown in fig. 4, the lead screw 3 employs a variable lead helix, and the lead in the low separating force region is large and the lead in the high separating force region is small. In fig. 4, the lead of the low separating force zone is denoted as L2 and the lead of the high separating force zone is denoted as L1, as shown in fig. 4, L1 is smaller than L2. That is, the sizes and heights described herein are relative.

As shown in fig. 5, when a variable lead spiral is used, rapid separation can be achieved in a low separation force region, improving separation efficiency; in a high separating force area, a spiral line with a small lead can obtain larger separating force, so that separation is better realized, and the reliability of separation is ensured.

In addition, as shown in fig. 6 and 7, one end of the nut sleeve 2 may be provided with a reverse spiral 25 to form a self-lock with the lead screw 3 at the end of disengagement, thereby maintaining the electronic clutch in a normally open state. If the reverse spiral line 25 is located at the forward end of the forward spiral line 24 in the advancing direction as viewed in the spiral direction of the nut case 2, the forward spiral line 24 and the reverse spiral line 25 are in opposite directions, as shown in fig. 6.

Therefore, on the occasion that the electronic clutch needs to be normally opened, the motor is not required to be always in a working state to provide the self-locking force for stabilizing the electronic clutch in the normally opened state, and the energy is saved. And, the mechanical auto-lock of screw sleeve 2 and lead screw 3 is realized through the structural improvement of screw sleeve 2, and is more reliable for providing the self-locking power through the motor relatively. Moreover, only a small section of reverse spiral line is needed to be arranged at the end part of the nut sleeve 2, and the structure is simple.

When the reverse spiral 25 is provided, as shown in fig. 7, the forward spiral 24 applies a downward oblique force F2 to the screw rod 3, and the reverse spiral 25 applies an upward oblique force F1 to the screw rod 3, so that the F1 is shifted to the end of the F2 in the direction shown by the dotted line in fig. 7, and a resultant force F is obtained, which is in the axial direction and pushes the screw rod 3 backward. At this time, the screw rod 3 only receives axial acting force, and component force in other directions does not exist, so that the screw rod cannot continuously perform spiral motion relative to the nut sleeve 2, and self-locking can be realized under the action of backward axial force. The rearward direction referred to herein means that the power source 4 is directed in the axial direction from the splitter cylinder 1.

Although fig. 4-6 show a position of the reverse spiral line 25 and a manner of arranging the variable-lead spiral line on the lead screw 3, it should be understood by those skilled in the art that the reverse spiral line 25 and the manner of changing the lead are not limited to the embodiment shown in the drawings, and the direction or the manner of changing the arrangement may be changed according to the use requirement.

On the basis, the invention also provides an electronic clutch which comprises the separation system. In view of the fact that the present application is primarily directed to improvements in the disconnect system, only the disconnect system is described herein, and other configurations of the electronic clutch are described with reference to the prior art and will not be described herein.

The electronic clutch and the disengagement system thereof provided by the present invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the core concepts of the present invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Claims

1. The separating system of the electronic clutch comprises a separating cylinder (1) and is characterized by also comprising a lead screw pair, wherein a nut sleeve (2) of the lead screw pair is fixedly connected with a piston rod (11) of the separating cylinder (1), and a lead screw (3) of the lead screw pair is connected with a power source (4) for driving the lead screw pair to rotate; the power source (4) drives the screw rod (3) to rotate so as to drive the nut sleeve (2) to axially move along the screw rod (3) and further push the piston rod (11) to execute a separating action; the nut sleeve (2) is connected with an elastic piece (5) in a pre-compression state, and when the nut sleeve (2) pushes the piston rod (11) to perform a separation action, the elastic piece (5) provides an auxiliary pushing force; one end of the nut sleeve (2) is provided with a reverse spiral line so as to form self-locking with the screw rod (3) at the final stage of separation and maintain the electronic clutch in a normally open state; the lead screw pair is a ball screw pair, the ball screw pair adopts a variable lead spiral line, and the lead in a low separating force area is large, and the lead in a high separating force area is small.

2. The disengagement system of an electronic clutch according to claim 1, characterized in that the power source (4) is an electric motor, the output shaft (41) of which is connected to the input of the screw (3) via a reduction gear set (6).

3. The disengagement system of an electronic clutch according to claim 2, characterized in that the reduction gear set (6) is a planetary gear set, comprising a sun gear (61) sleeved on the output shaft (41) and at least one stage of planetary gears (62) meshed with the sun gear (61), and the output end of the planetary gear (62) at the final stage is fixedly connected with the input end of the screw rod (3).

4. A release system for an electronic clutch according to claim 3, characterised in that the reduction gear set (6) is provided with at least two final planetary wheels (62), the output of each final planetary wheel (62) being fixedly connected to the input of the spindle (3) at circumferentially spaced intervals.

5. Release system for an electronic clutch according to one of claims 1 to 4, characterized in that a first flange (31) is fixedly connected to the input of the screw (3), a second flange (21) arranged opposite the first flange (31) is fixedly connected to the nut sleeve (2), and the elastic element (5) is axially pre-compressed between the first flange (31) and the second flange (21).

6. The disengagement system of the electronic clutch according to claim 5, characterized in that the elastic member (5) is a leaf spring fitted over the nut sleeve (2); the sleeve (22) of the nut sleeve (2) extends in the axial direction of the screw rod (3) to support the elastic piece (5).

7. The electronic clutch release system according to claim 5, wherein the nut sleeve (2) is a cylinder with an open end, the open end of the nut sleeve (2) is used to fit the lead screw (3) inside, the closed end is provided with a connector (23), and the piston rod (11) has a connecting hole fixedly matched with the connector (23).

8. The release system of an electronic clutch according to any one of claims 2 to 4, characterized by further comprising a housing (7) having a hollow cavity (71), wherein both ends of the housing (7) are connected to the release cylinder (1) and the motor, respectively, so as to enclose the reduction gear set (6), the lead screw (3), the nut sleeve (2) and a portion of the release cylinder (1) within the hollow cavity (71) of the housing (7).

9. Electronic clutch, characterized in that it comprises a release system according to any of the preceding claims 1-8.