CN107882458A - Torsion overload protection device - Google Patents

Abstract

The invention discloses a torque overload protection device, which comprises a sleeve, a pair of transmission shafts, a pair of clutch discs, a plurality of roller pins and an elastic piece. The pair of transmission shafts are respectively arranged at two ends of the sleeve in a penetrating way along the axial direction of the sleeve, and the pair of transmission shafts are mutually separated and coaxially arranged. The pair of clutch discs are respectively arranged in the sleeve in a penetrating way and are arranged oppositely, each clutch disc is respectively linked with each transmission shaft to rotate, and one clutch disc can move along the axial direction of the sleeve. The rolling needles are clamped between the pair of clutch discs, and two ends of each rolling needle are spherical surfaces and are respectively embedded into the clutch discs. The elastic piece is used for pushing the pair of clutch discs, and the elastic piece is connected between the inner wall of the sleeve and the movable clutch discs. When the torsion is overloaded, the roller pin can slip from the clutch disc. The invention can slip from the clutch disc when the torsion is overloaded by the roller pin to interrupt the power connection between the driving component and the screw rod, thereby avoiding the damage of the component caused by the torsion overload.

Description

Torque overload protection device

technical field

The invention relates to a torsional overload protection device, in particular to a needle-type torsional overload protection device.

Background technique

A general electric vehicle tailgate retractable ejector rod includes an outer tube, an inner tube, a screw rod, an inner tooth sleeve and a motor, the inner tube is installed inside the outer tube, the screw rod is installed inside the inner tube, and the inner screw rod is installed inside the inner tube. The sleeve is connected to the inner tube and engages with the screw, and the motor can drive the screw to rotate, and the rotation of the screw can move the inner sleeve along the screw, thereby driving the inner tube to expand and contract relative to the outer tube and can be used to open and close the tailgate of the car. The tailgate of a car has considerable weight, and the telescopic ejector rod bears a considerable weight load. When the output torque of the motor is too large, the ejector member may be damaged.

Contents of the invention

The invention provides a needle-type torsional overload protection device, which is used to be connected between the driving assembly and the screw rod of the telescopic push rod of the tailgate of the automobile, and is used to transmit the power of the driving assembly to the screw rod.

The invention provides a torsional overload protection device, comprising:

a sleeve;

A pair of transmission shafts are respectively installed on the two ends of the sleeve along the axial direction of the sleeve, and the pair of transmission shafts are separated from each other and arranged coaxially;

A pair of clutch discs are respectively installed in the sleeve and the pair of clutch discs are opposite to each other. Each of the clutch discs rotates in conjunction with each of the transmission shafts, and one of the clutch discs can move along the axis of the sleeve. to move;

A plurality of needle rollers are interposed between the pair of clutch discs, and the two ends of each of the needle rollers are spherical and embedded in the respective clutch discs; and

An elastic member for pushing the pair of clutch discs closer is connected between the inner wall of the sleeve and the movable clutch disc.

Wherein each of the clutch discs has a transmission surface and the two transmission surfaces are oppositely arranged, and the two ends of each of the needle rollers are respectively embedded in each of the transmission surfaces.

One of the transmission surfaces is provided with a plurality of dimples corresponding to each of the needle rollers, and one end of each of the needle rollers is respectively inserted into the corresponding dimples.

The other transmission surface is provided with a plurality of grooves corresponding to the needle rollers, and the other ends of the needle rollers are accommodated in the corresponding grooves.

Wherein the edges of each of the pits respectively form a guide slope.

Wherein the plurality of dimples are arranged around the pair of transmission shafts.

Wherein the elastic member is a cylindrical spring sheathed on one of the transmission shafts, one end of the elastic member abuts against one end of the sleeve, and the other end of the elastic member abuts against the axially movable clutch disc.

Wherein the pair of clutch discs are relatively nested.

The torsional overload protection device of the present invention can slip off from the clutch disc to interrupt the power connection between the drive assembly and the screw rod when the torsional overload is caused by the needle roller, so as to avoid damage to components due to torsional overload.

Description of drawings

Fig. 1 is a schematic configuration diagram of a torsional overload protection device according to a preferred embodiment of the present invention.

Fig. 2 is a three-dimensional exploded schematic diagram of a torsional overload protection device according to a preferred embodiment of the present invention.

Fig. 3 is a diagram of a use state of the torsional overload protection device according to the preferred embodiment of the present invention.

Fig. 4 is another usage state view of the torsional overload protection device according to the preferred embodiment of the present invention.

In the picture:

10 outer tube;

20 inner tube;

30 screw;

40 inner teeth sleeve;

50 drive components;

100 sleeves;

200 drive shaft;

210 power input shaft;

220 power output shaft;

300 clutch disc;

310 power input plate;

311 transmission surface;

312 pits;

313 guide slope;

320 PTO;

321 transmission surface;

322 tanks;

400 needle rollers;

500 elastic.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and implement it, but the examples given are not intended to limit the present invention.

Referring to Fig. 1, a preferred embodiment of the present invention provides a torsional overload protection device for a telescopic push rod of an automobile tailgate. The telescopic push rod of the automobile tailgate comprises an outer tube 10, an inner tube 20, a screw rod 30, and an inner tooth sleeve 40 (for example, a nut or a sleeve provided with inner screw teeth, which can be made of metal or plastic. ) and a drive assembly 50, the inner tube 20 is threaded inside the outer tube 10, the screw 30 is threaded inside the inner tube 20, the inner tooth sleeve 40 is connected to the inner tube 20 and engages the screw 30, and the drive assembly 50 can drive the screw 30 Rotate (the driving assembly 50 can be a motor or further include gears, worm gears or other transmission components connected between the screw 30 and the motor), the rotation of the screw 30 can make the inner sleeve 40 move along the screw 30, thereby driving the inner The pipe 20 can be used to open and close the door by expanding and contracting with respect to the outer pipe 10 . The torsional overload protection device of the present invention is connected between the drive assembly 50 of the ejector rod and the screw 30 to transmit the power of the drive assembly 50 to the screw 30, and when the torque provided by the drive assembly 50 or the instantaneous load exceeds When it is large, the torsional overload protection device of the present invention can interrupt the power connection between the driving assembly 50 and the screw rod 30, thereby avoiding damage to the mechanism.

Referring to FIGS. 1 to 3 , the torsional overload protection device of the present invention includes a sleeve 100 , a pair of transmission shafts 200 , a pair of clutch discs 300 , an elastic member 500 and a plurality of needle rollers 400 .

In this embodiment, the sleeve 100 is preferably a cylindrical shell, and one end of the sleeve 100 is constituted by a part of the casing of the aforementioned driving assembly 50 .

One of the pair of transmission shafts 200 is a power input shaft 210 , and the other is a power output shaft 220 . The power input shaft 210 is connected with the driving assembly 50 and penetrates the sleeve 100 from one end of the sleeve 100 ; the power input shaft is connected with the screw rod 30 and penetrates the sleeve 100 from the other end of the sleeve 100 . The power input shaft 210 and the power output shaft 220 are arranged coaxially along the axial direction of the sleeve 100 and separated from each other.

The pair of clutch discs 300 are passed through the sleeve 100 and the pair of clutch discs 300 are relatively fitted together. One of the clutch discs 300 is a power input disc 310 , and the other clutch disc 300 is a power output disc 320 . The power input disc 310 and the power output disc 320 are fitted together so that they can move axially relative to each other. The power input shaft 210 passes through the center of the power input disc 310 and rotates in conjunction with the power input disc 310. The power output shaft 220 passes through the power input disc 310. The center of the output disk 320 rotates in conjunction with the power output disk 320, and one of the clutch disks 300 can move along the axial direction of the sleeve 100. In this embodiment, the power input disk 310 can move along the axial direction of the sleeve 100 , the power output disk 320 is fixed along the axial direction of the sleeve 100, but the present invention is not limited thereto, and the power output disk 320 can be moved along the axial direction of the sleeve 100. The axial direction of the sleeve 100 is fixed.

Each clutch disc 300 (310, 320) has a transmission surface 311, 321 respectively, and the pair of transmission surfaces 311, 321 are arranged oppositely. A plurality of pits 312 are provided on the transmission surface 311 of the power input disc 310. The power output disc 320 A plurality of receiving grooves 322 are defined on the transmission surface 321 . The dimples 312 are shallow and flat concave structures, and edges of each dimple 312 respectively form a guide slope 313 . The number of the pits 312 corresponds to the number of the holding grooves 322, and the plurality of pits 312 are arranged around the center of the power input disc 310 and arranged around the pair of transmission shafts 200 (210, 220), and the plurality of holding grooves 322 also surround The configuration of the power take-off disk 320 is arranged around the pair of transmission shafts 200 (210, 220). Wherein, the dimple 312 and the receiving groove 322 can also be arranged interchangeably, and the present invention is not limited thereto.

In this embodiment, the number of the needle rollers 400 preferably corresponds to the number of the pits 312 and the grooves 322. The plurality of needle rollers 400 are sandwiched between the pair of clutch discs 300, and each needle roller 400 The two ends are spherical and respectively embedded in the driving surfaces 311, 321 of the clutch discs 300 (310, 320), but the present invention is not limited thereto. One end of each needle roller 400 is inserted into the corresponding recess 312 , and the other end of the needle roller 400 is accommodated in the corresponding cavity 322 . In the torsional overload protection device of the present invention, one end of each needle roller 400 is accommodated in the cavity 322 of one of the clutch discs 300 (in this embodiment, the power take-off disc 320 ) and is connected to the clutch disc 300 ( The power output disc 320) is connected, and the other end of the needle roller 400 abuts against the guide slope 313 of the recess 312 of the other clutch disc 300 (in this embodiment, the power input disc 310).

The elastic member 500 is connected between the inner wall of the sleeve 100 and the axially movable clutch disc 300, and is used to push the axially movable clutch disc 300 to the other clutch disc 300 so that the pair of clutch discs 300 clamp the roller. The needle 400 , so that there is enough friction between the needle roller 400 and the guide slope 313 to make the pair of clutch discs 300 rotate in unison. In this embodiment, the elastic member 500 is a cylindrical spring sleeved on the power input shaft 210, and one end of the elastic member 500 abuts against one end of the sleeve 100 (in this embodiment, since one end of the sleeve 100 is formed by the drive assembly 50, so the elastic member 500 abuts against the outer casing of the driving assembly 50), and the other end of the elastic member 500 abuts against the axially movable clutch disc 300. The friction force between the needle roller 400 and the guiding slope 313 can be adjusted to a predetermined allowable value by selecting the elastic coefficient of the elastic member 500 or selecting the slope of the guiding slope 313 .

Referring to FIG. 4 , when the torque is overloaded, the frictional force between the needle roller 400 and the guide slope 313 is insufficient to balance the torque provided by the driving assembly 50 , so that the needle roller 400 slips out of the recess 312 . The spherical end surface of the slipped needle roller 400 is in single-point contact with the transmission surface 311 of the power input disk 310, so the friction force between the needle roller 400 and the transmission surface 311 of the power input disk 310 is extremely small, and the needle roller 400 can move on the power input disk 310. Sliding on the transmission surface 311 of 310. When the slipped needle roller 400 slips to the next recess 312, if the torque provided by the drive assembly 50 is still overloaded, the needle roller 400 slips again until the torque provided by the drive assembly 50 is reduced to a permissible value (drive assembly 50 The torque provided is smaller than the frictional force between the needle roller 400 and the guide slope 313 ), the needle roller 400 can be embedded in the recess 312 to make the power input shaft 210 and the power output shaft 220 rotate in unison.

Therefore, the torsional overload protection device of the present invention can interrupt the power connection between the drive assembly 50 and the screw rod 30 when the torsional overload of the tailgate telescopic push rod is overloaded by the aforementioned structure, so as to avoid damage to components due to torsional overload.

The above-mentioned embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention. The protection scope of the present invention shall be determined by the claims.

Claims (8)

1. a kind of torque force overload protection device, it is characterised in that include：

One sleeve；

A pair of power transmission shafts, two ends of the sleeve are located in respectively along the axial direction of the sleeve, and a pair of power transmission shafts be separated from each other and It is coaxially disposed；

A pair of clutch discs, are located within the sleeve respectively and a pair of clutch discs are oppositely arranged, respectively the clutch discs respectively with respectively The transmission shaft linkage rotates, and wherein one clutch discs can be along the axial movement of the sleeve；

Multiple needle rollers, this is folded between clutch discs, two ends of each needle roller for sphere and are respectively embedded into the respectively clutch discs； And

To an elastic component of push away near a pair of clutch discs, be connected to the inwall of the sleeve and the clutch discs that can move it Between.

2. torque force overload protection device according to claim 1, it is characterised in that wherein respectively the clutch discs have one respectively Driving face and two driving faces are oppositely arranged, two ends of each needle roller are respectively embedded into the respectively driving face.

3. torque force overload protection device according to claim 2, it is characterised in that corresponding each on one of them driving face The needle roller offers multiple pits, and respectively one end of the needle roller is respectively embedded within the corresponding pit.

4. torque force overload protection device according to claim 3, it is characterised in that corresponding on the other in which driving face Respectively the needle roller offers multiple tanks, and respectively the other end of the needle roller is respectively contained within the corresponding tank.

5. torque force overload protection device according to claim 3, it is characterised in that wherein respectively shape is distinguished at the edge of the pit It is domatic into a guiding.

6. torque force overload protection device according to claim 3, it is characterised in that wherein the plurality of pit is around this pair Drive shaft arrangements.

7. torque force overload protection device according to claim 1, it is characterised in that wherein the elastic component is to be arranged wherein The column spring of one power transmission shaft, one end of the elastic component abut one end of the sleeve, and the other end of the elastic component abuts can The clutch discs of axial movement.

8. torque force overload protection device according to claim 1, it is characterised in that wherein a pair of clutch discs are with respect to fit Set.