CN108071747B

CN108071747B - Dual mass flywheel

Info

Publication number: CN108071747B
Application number: CN201610983374.9A
Authority: CN
Inventors: 董野; 刘春晖; 张明阳
Original assignee: Nanjing Valeo Clutch Co Ltd
Current assignee: Nanjing Valeo Clutch Co Ltd
Priority date: 2016-11-10
Filing date: 2016-11-10
Publication date: 2021-08-10
Anticipated expiration: 2036-11-10
Also published as: CN108071747A

Abstract

The invention relates to a dual mass flywheel comprising a primary mass body, a secondary mass body and a detachable connecting device, wherein the connecting device rigidly connects the primary mass body and the secondary mass body in the mounted state. Through the detachable connecting device, the primary mass body and the secondary mass body can be rigidly connected during the bench test of the engine, for example, and after the bench test is finished, the connecting device is detached to restore the dual-mass flywheel to a normal working state, so that the requirement of the engine test is met.

Description

Dual mass flywheel

Technical Field

The present invention relates to a dual mass flywheel, and more particularly to a dual mass flywheel capable of detachably rigidly connecting a primary mass body and a secondary mass body.

Background

Generally, a flywheel, which is made of, for example, cast steel, has a certain mass, is fixed to a rear end surface of a crankshaft of an engine by an engine bolt, and has teeth on an outer periphery thereof to mesh with a starter gear or the like to rotationally start the crankshaft, is provided at a rear end of the engine of a vehicle. The flywheel not only functions at engine start but also stores and releases energy to improve uniformity of engine operation after engine start while transferring engine power to the clutch.

However, such a conventional flywheel has a limitation that the natural frequency between the engine and the transmission cannot be reduced below the idle speed, and the possibility of resonance at the idle speed cannot be avoided, and further, since the torsional damper is provided in the clutch, the spring rate of the damper cannot be reduced, and the damping effect is poor, and therefore, a Dual Mass Flywheel (DMF) has been proposed in recent years.

A dual mass flywheel generally comprises a primary mass body, which remains in position on one side of the primary engine and acts as the primary flywheel for starting and transmitting the rotational torque of the engine, and a secondary mass body, which increases the rotational inertia of the transmission, between which an annular chamber is provided in which a spring damper is arranged to connect the two mass bodies together. The secondary mass body can improve the inertia moment of the transmission system on the premise of not increasing the inertia moment of the flywheel, so that the resonance rotating speed can be reduced to be lower than the idle rotating speed. That is, in any case, the resonance rotational speed is below the rotational speed range in which the engine operates. In addition, the separation and coupling of the secondary mass of the dual mass flywheel from the transmission can be achieved by a rigid clutch disc without damper, so that the mass of the clutch is significantly reduced, the synchronization is improved and the shifting is facilitated.

Although dual mass flywheels may function well during vehicle operation, there is a situation where it may be desirable in some bench tests prior to engine shipment, particularly in cold and hot engine start-up bench tests, to maintain a rigid connection between the two masses of a dual mass flywheel to verify certain operating conditions of the engine. A need has therefore arisen to rigidly connect the primary and secondary masses of a dual mass flywheel in a bench test and to restore the flexible connection of the primary and secondary masses after the bench test.

Disclosure of Invention

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a detachable connection device capable of rigidly connecting a primary mass body and a secondary mass body of a dual mass flywheel at the time of engine bench test and easily detaching after bench test, restoring flexible connection of the primary mass body and the secondary mass body.

According to one aspect, the present invention provides a dual mass flywheel comprising: a primary mass, a secondary mass and a detachable connection, wherein the connection rigidly connects the primary mass and the secondary mass in the mounted state.

Through detachable connecting device, when carrying out engine bench test, can be with the elementary quality body and the secondary quality body rigid connection of dual mass flywheel to connecting device can be dismantled by convenient and swiftly when bench test is accomplished, with resume normal operating condition with dual mass flywheel fast.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a side sectional view showing the main structure of a conventional dual mass flywheel;

fig. 2 is a side sectional view showing a dual mass flywheel according to a first embodiment of the present invention;

FIG. 3 is a side cross-sectional view illustrating a coupling included in the dual mass flywheel shown in FIG. 2;

FIG. 4 is a perspective view showing the connector shown in FIG. 3;

FIG. 5 is a front view showing a dual mass flywheel according to a second embodiment of the present invention;

FIG. 6 is a perspective view showing the hub (hub) in a dual mass flywheel;

fig. 7 is a perspective view showing a spacer (spacer) in the dual mass flywheel;

FIG. 8 is a side cross-sectional view illustrating a dual mass flywheel according to a second embodiment of the present invention;

fig. 9 is a partial view showing a dual mass flywheel according to a third embodiment of the invention;

FIG. 10 is a cut-away perspective view showing the dual mass flywheel of FIG. 9 from a different angle; and

fig. 11 is a side sectional view showing a dual mass flywheel according to a third embodiment of the present invention.

Detailed Description

Embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Throughout the drawings, the same reference numerals are used to designate the same or similar elements or components.

Thus, the following detailed description of the embodiments of the present invention, presented in conjunction with the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "upper side", "lower side", "inside", "outside", and the like indicate orientations or positional relationships based on those shown in the drawings, or orientations or positional relationships that are conventionally placed when the products of the present invention are used, or orientations or positional relationships that are conventionally understood by those skilled in the art, and are used merely for convenience of description and simplification of the description, and do not indicate or imply that the equipment or elements that are referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the invention. In addition, it is still to be understood that the term "connected" in describing the present invention may include not only a direct connection of one element, component or feature to another element, component or feature, but also an indirect connection of one element, component or feature to another element, component or feature through intermediate elements, components or features. And the term "directly connected" does not include such intervening elements.

Referring now to fig. 1, a dual mass flywheel is briefly described. The dual mass flywheel basically comprises a primary mass 1, a secondary mass 2 and a spring 3 connected between the primary mass 1 and the secondary mass 2. The primary mass body 1 is fixed to a crankshaft of an engine (not shown) by, for example, bolts or the like, and rotates together with the crankshaft of the engine. In addition, as shown in fig. 1, the primary mass body 1 includes a spacer 4, and the secondary mass body 2 includes a hub 5, the hub 5 being provided with, for example, a spline hole 51 to connect with an input shaft of a transmission (not shown).

A dual mass flywheel 10 according to a first embodiment of the invention is described below with reference to fig. 2 to 4.

Similar to that described with reference to fig. 1, the dual mass flywheel 10 according to the first embodiment of the present invention includes a primary mass body 1, a secondary mass body 2, and a spring 3 (see fig. 1) connected between the primary mass body and the secondary mass body. In addition, the dual mass flywheel 10 further includes a coupling device 20.

As shown in fig. 2, the connecting device 20 includes a plurality of connecting members 22 (only one shown). Referring to fig. 4, the connector 22 includes a cylindrical portion 23 having one end closed, and at the bottom of the cylindrical portion 23, a protrusion 24 extending outward is provided, and in the sidewall of the cylindrical portion, a slit 25 is provided so that the sidewall may have certain elasticity. In addition, in a substantially central position of the bottom, a threaded hole 26 is provided for cooperation with a removal screw 27, and extends through the projection 24, forming a through hole. Alternatively, the threaded hole 26 may be formed with threads only on a portion of its length. That is, a thread is formed in a portion of the threaded hole located in the bottom portion, and a light hole of a larger diameter is formed in a portion located in the protruding portion 24.

Referring to fig. 2, the operation of the connecting member 22 will be described. As shown in fig. 1, the primary mass body 1 is provided with a spacer 4, and the spacer 4 is connected to an engine crankshaft (not shown) by an engine bolt 28 (see fig. 2 to 3). As shown in fig. 1 and 5, the secondary mass body 2 is provided with a hub 5, and the hub 5 includes a central splined hole 51 and lightening holes 52 (see fig. 6) provided around the central splined hole 51.

Referring to fig. 2, the connecting members 22 may be inserted into the lightening holes 52 of the hub 5 at equal angular intervals, respectively, such that the side walls of the cylindrical portion are closely fitted with the lightening holes 52 by virtue of the elasticity of the slits 25 in the side walls. Preferably, a taper may be provided on a portion or all of the cylindrical portion to facilitate insertion of the cylindrical portion into the lightening hole. As the connecting members 22 are inserted down into the lightening holes 52 of the hub 5, the protrusions 24 of the connecting members 22 are inserted into the recesses on the heads of the corresponding engine bolts 28 and tightly abut against the recesses as the connecting members 22 are further inserted, thereby rigidly connecting the primary mass body 1 with the secondary mass body 2 through a plurality of (e.g., 3) connecting members 22 for bench testing.

After the bench test is finished, in order to detach the attachment member 22, the detachment screw 27 may be screwed into the threaded hole 28 formed in the bottom of the cylindrical portion, as shown in fig. 2, the detachment screw 27 passes through the bottom and its tip abuts against the bottom surface of the recess in the head of the engine bolt 28, and as the detachment screw 27 is screwed, the attachment member 22 is pushed out of the lightening hole 52 by the interaction between the threaded portion of the detachment screw 27 and the threaded hole 28 of the attachment member, thereby detaching the attachment member 22, so that the dual mass flywheel is restored to the normal operating state.

Although the dual mass flywheel according to the first embodiment of the present invention is described above with reference to the drawings, the present invention is not limited thereto. For example, a plurality of the connection members 22 may be provided, not necessarily limited to three. Further, it is noted that in fig. 2 and 3, the protrusion 24 is provided in the form of a frustum having a circular cross section, but the protrusion 24 may also be provided to have the same cross section as that of the groove on the head of the engine bolt. For example, in the case where the recess of the bolt head is shaped as an internal hexagon, the projection 24 may be provided with a hexagonal cross-section to mate with the hexagonal recess. The protrusion 24, which is configured to have a circular cross-section, may accommodate various groove shapes. In addition, instead of the removal screw 27, another removal structure may be adopted, for example, a portion that engages with a tool may be provided inside the bottom of the cylindrical portion so as to engage with a tool such as nipper pliers to pull the connecting member 22 out of the lightening hole.

In the first embodiment, the connecting member 22 can rigidly connect the primary mass body and the secondary mass body by using the existing lightening holes and engine bolts of the dual mass flywheel, thereby eliminating the step of additionally processing the primary mass body (spacer) and the secondary mass body (hub), simplifying the manufacturing process and saving the cost.

A dual mass flywheel 10' according to a second embodiment of the present invention is described below with reference to fig. 4 to 8. Since the dual mass flywheel 10' according to the second embodiment is identical to the dual mass flywheel 10 according to the first embodiment of the present invention described above except for the connecting means, only the differences therebetween will be described below, and the duplicated description will be omitted for the sake of brevity.

The difference from the dual mass flywheel 10 described above according to the first embodiment of the invention is that: in the present embodiment, the connecting device 20' employs a fixed pendulum (fixing pendulum) system.

As shown in fig. 7 and 8, the connecting device 20 ' includes bolts 22 ' and 22 ' arranged opposite to each other (i.e., spaced 180 ° from each other), and an irregularly shaped spacer 23 connected between the two bolts 22 ' and 22 ', specifically, the spacer 23 is substantially elongated in shape, and through holes (not shown) into which the bolts 22 ' and 22 ' are respectively inserted are provided on both ends of the spacer 23. And in order to connect the primary mass body 1 and the secondary mass body 2, as shown in fig. 5 and 6, in the hub 5, through holes 24 ' and 24 ' are provided at diametrically opposite positions, i.e., at two positions spaced 180 ° apart, and screw holes 25 ' and 25 ' are provided at corresponding positions of the spacer 4, whereby bolts 22 ' and 22 ' can be respectively passed through the through holes on both ends of the spacer 23 and the through holes 24 ' and 24 ' on the hub 5 and screwed into the screw holes 25 and 25 ' of the spacer 4. For anti-loosening, a spring washer 26 may be provided between the head of the bolts 22' and the washer 23.

The primary mass body 1 and the secondary mass body 2 can be rigidly connected by screwing the bolts 22 'and 22' into the threaded holes 25 'and 25' of the spacer 4 through the through holes 24 'and 24' on the hub 5, respectively, so that the primary mass body 1 and the secondary mass body 2 of the dual mass flywheel are brought to rotate together when the engine is rotated.

For example, after the engine bench test is finished, the bolts 22 'and 22' can be loosened simply by a tool such as a wrench, and the primary mass body 1 and the secondary mass body 2 can be disengaged to return to the normal operating state.

By providing the two bolts 22 'and 22' in opposite positions, i.e. at 180 ° intervals from each other, the unbalanced mass generated when the dual mass flywheel rotates can be reduced compared to the above-described embodiment. Also, by providing the spacer 23 between the two bolts, the two bolts 22 'and 22' can be taken out together from the dual mass flywheel after the bolts 22 'and 22' are loosened, and the bolts are prevented from falling into the dual mass flywheel. Furthermore, by providing the spacer 23 between the two bolts 22 ' and 22 ', the spacer 23 straddles the splined hole 51 of the hub 5, so that when the dual mass flywheel is assembled with the input shaft of the transmission, the spacer 23 interferes with the input shaft of the transmission to make the dual mass flywheel and the transmission unable to be assembled in the presence of the bolts 22 ' and the spacer 23. Therefore, it is possible to avoid the occurrence of forgetting to detach the bolts 22 'and 22' due to carelessness.

A dual mass flywheel 10 "according to a third embodiment of the invention is described below with reference to fig. 9 to 11. Since the dual mass flywheel 10 ″ according to the third embodiment is identical to the dual mass flywheel 10 according to the first embodiment of the present invention described above except for the connecting means, only the differences therebetween will be described below, and the duplicated description will be omitted for the sake of brevity.

The dual mass flywheel 10 "according to the present embodiment differs from the dual mass flywheel 10 according to the first embodiment in the specific structure of the connecting means. In the dual mass flywheel 10 "according to the present embodiment, the connecting means 20" comprises a plurality of (generally three) pins 22 ", said three pins 22" being arranged at equal intervals around the hub 5 and being inserted with interference into holes formed in the hub 5 and in the spacer 4, respectively, see fig. 10 and 11, and preferably said pins 22 "leaving a portion on the outside of the hub 5. The primary mass 1 and the secondary mass 2 of the dual mass flywheel 10 "are rigidly connected by means of the pin 22" and thus rotate together with one another in the engine bench test.

After e.g. the bench test has been completed, the pin 22 "can be easily pulled out of the holes of the spacer 4 and the hub 5 by clamping the part of the pin 22" remaining outside the hub with a tool such as a nipper pliers, thereby restoring the dual mass flywheel to a normal operating condition.

The invention has been described above by means of three preferred embodiments of the invention, but it is to be understood that the invention is not limited to the embodiments described above, but that various modifications or variations are possible within the scope defined by the appended claims. For example, the above-mentioned number is not limited to two or three, but may be four or more, as long as it can be ensured that the dual mass flywheel maintains rotational balance during rotation. Accordingly, the scope of the present invention is not limited by the above-described embodiments, but is defined by the appended claims and equivalents thereof.

Claims

1. A dual mass flywheel comprising a primary mass, a secondary mass and a detachable connection means, wherein the connection means rigidly connects the primary mass and the secondary mass in the mounted state,

wherein the primary mass comprises a spacer and the secondary mass comprises a hub, the connecting means rigidly connecting the spacer and the hub in the mounted state, an

The hub comprises a plurality of lightening holes which are uniformly arranged at intervals on the circumference, the spacing piece is connected with a crankshaft of an engine through a plurality of engine bolts, and the connecting device comprises a plurality of connecting pieces which are respectively arranged in the lightening holes and are simultaneously and respectively inserted into the grooves of the heads of the corresponding engine bolts.

2. A dual mass flywheel as defined in claim 1 in which each said connecting member includes a cylindrical portion with a bottom portion and a projection extending outwardly from said bottom portion, said cylindrical portion fitting closely within said lightening hole and said projection being inserted into and abutting closely with a recess in the head of said engine bolt.

3. The dual mass flywheel of claim 2, wherein a slit is provided in a sidewall of the cylindrical portion to make the cylindrical portion elastic.

4. A twin mass flywheel as defined in claim 2 in which part or all of the cylindrical portion is tapered.

5. The dual mass flywheel of claim 2, wherein the protrusion has a circular cross-section.

6. A twin mass flywheel as defined in any one of claims 2 to 5 in which the base is provided with a threaded bore which extends through the projection.

7. A twin mass flywheel as defined in claim 6 in which the threaded bore is threaded over only a portion of its length.

8. The dual mass flywheel of claim 6, wherein the attachment means further comprises a knockout bolt that can be threaded through the threaded bore.

9. The dual mass flywheel of claim 7, wherein the attachment means further comprises a knockout bolt that can be threaded through the threaded bore.