US3548964A - Device for the limitation of the movements of an elastically suspended drive unit - Google Patents

Description

United States Patent [72] Inventors Heinz Krauss Appl. No. Filed Patented Assignee Priority Korb Kreis, Waiblingen;

Wolfgang Sautter, Heimerdlngen, Wuerttemberg; Uwe Llgniez, Waiblingen, Germany June 13, 1968 Dec. 22, 1970 Daimler-Benz Aktlengesellschaft Stuttgart-Unterturkheim, Germany June 15, 1967 Germany DEVICE FOR THE LIMITATION OF THE MOVEMENTS OF AN ELASTICALLY SUSPENDED DRIVE UNIT 24 Claims, 9 Drawing Figs.

US. Cl 180/64, 248/9 Int. Cl. 860k 5/12 Field of Search 1 80/64;

[56] References Cited UNITED STATES PATENTS 2,080,435 5/ 1937 Paton 180/64 2,084,080 6/1937 DAubarede 180/64 2,270,902 1/1942 Rubissow 248/ 8X 2,406,256 8/1946 Roche 248/9 3,244,386 4/1966 Bourgeois 248/9 FOREIGN PATENTS 603,643 6/1948 Great Britain 180/64 Primary Examiner- Banjamin Hersh Assistant Examiner-Milton L. Smith Attorney-Craig, Antonelli, Stewart & Hill ABSTRACT: An arrangement for limiting the stroke movements of an elastically suspended drive unit, in which the elastic abutment or abutments are so arranged in or nearly within a vertical longitudinal center plane of the drive unit that in the vertical direction they come into abutment after traversing a limited, free deflection path whereas in the direction of rotation about the longitudinal axis, i.e., in particular under the effect of the engine torque, normally, they fail to come into abutment.

PATENTED DEB22 mm 3.54 35 sum 1 UF 2 I INVENTORS HEINZ muss WOLFGANG SAUTTER UWE LIGNIEZ ATTORNEYS DEVICE FOR THE LIMITATION OF THE MOVEMENTS OF AN ELASTICALLY SUSPENDED DRIVE UNIT The present invention relates to a device for the stroke limitation of an elastically suspended drive unit. Stops for the stroke limitation were arranged heretofore laterally of the engine with as large as possible a lever arm' with respect to the engine longitudinal axis in order to absorb the torques and torque fluctuations occurring during operation, and were so adjusted that they came into abutment under the torque. As a result thereof, humming'noises occurred in the vehicle interior by reason of the sound transmission, which considerably impaired the driving comfort.

It is the aim of the present invention above all to prevent or at least far-reachingly reduce the transmission of engine noises to the vehicle body. This is achieved according to the present invention in that the elastic stop or stops are so arranged in or nearly within a vertical longitudinal center plane of the unit that in the vertical direction they come'into abutment after a limited free oscillation or deflection path but do not come into abutment in the direction of rotation about the longitudinal axis of the unit, i.e., in particular under the effect of the engine torque. A noise or sound transmission as with the prior art types of constructions used heretofore, operating, for example, with engine movement shock absorbers or engine mounting rods is avoided in the state of quiescence of the unit by reason of the free swinging or pivot path. As compared to engine movement shock absorbers, the arrangement according to the present invention additionally causes considerably smaller costs with the same reduction of engine paths.

The elastic stop or stops may be located within a vertical transverse plane extending through the center of gravity of the drive unit, i.e., below or above the center of gravity. However, preferably the-stops or abutments are arranged in two transverse planes, in particular at the forward and at the rear end of the unit, approximately'in a vertical plane containing the engine longitudinal axis and below the engine longitudinal axis. As a rule, it is thereby insignificant whether the crankshaft axis, the main inertia axis or a pivot bearing support axis of the engine or engine unit is assumed as engine longitudinal axis because in general, all of these axes are disposed or are nearly disposed in a common vertical longitudinal plane.

A stop or abutment member freely adjustable into a center position is provided for the limitation of the'free swinging or deflection path. However, depending on the type of construction and requirements, the free swinging or deflection path can be selected differently and may be nearly zero in the limit case. It has been found as particularlyadvantageous if the free swinging or deflection path of the engine unit inrelatio'n to the remaining vehicle is larger in the downward direction (for example, 3 to mm.) than in the upward direction (for example, 0.5 to 2 mm.). The elastic stop surfaces or abutments elements may be arranged at the abutment part or at the counterabutment part or possibly also at both parts.

It is particularly advantageous to provide elastic abutments and/or a free swinging or deflection path, which are adjustable, so that a favorable play can be achieved and a subsequent correction thereof can, be undertaken. p

In a particularly preferred construction of the present invention, the freely adjustable abutment part or parts areconnected without play with one of the parts to be supported in a limited manner, for example, with the engine unit, and are connected with the other of these pans to be supported, for example, with a vehicle part, by means of elastic elements having slight resistance in the vertical direction whereby the lastmentioned part is provided with counterabutment elements, against which the abutment part or parts rest after traversing the free swinging or deflection path. The connection with the first-mentioned part may take place, for example, by means of connecting links or the like provided with adjusting means. For example, lateral elastic web elementsof rubber or the like serve for the connection with slight resistance with the second-mentioned part, which enable a free swinging and selfadjustment of the abutment part in the vertical direction. Such types of weblike elements are also particularly advantageous when the abutment part itself consists completely or nearly completely of rubber or similar material.

Possibly, a further yieldingness, for example, a universal yieldingness can be interposed between the elastic abutments and'one of the parts to be mutually supported. Additionally, the rubber forming the abutments may be provided at the abutment surfaces with a layer of suitable, known synthetic resinous material in order that it is protected against premature wear by the universal movements (stirring movements) occurring during the operation between the engine drive unit and the vehicle part.

Accordingly, it is anobject of the present invention to provide an arrangement for limiting the toand fro movements of an elastically suspended engine unit which obviates, by simple means, the aforementioned shortcomings and drawbacks encountered in the prior art.

It is another object of the present-invention to provide a device for limiting stroke movements of an elastically suspended drive unit which prevents'or at least far-reachingly reduces the transmission of sound to the body and therewith into the vehicle interior space. i

A further object of the present invention resides in a device for limiting the strokes of an elastically suspended drive unit which considerably improves the driving comfort.

A still further object of the present invention resides in an engine unit suspension of the type described above which permits the attainment of a favorable play with possible subsequent readjustment.

These and further objects, features, and advantagesof the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, several embodiments in accordance with the present invention, and wherein:

FIG. 1 is a schematic side elevational view of the overall arrangement of an engine drive unit in accordance with the present invention;

FIG. 2 is a side elevational view, partly in cross section and on an enlarged scale, of a stroke-limiting arrangement in accordance with the present invention, corresponding approximately to the forward stroke-limiting device of FIG. 1; 7

FIG. 3 is a side elevational view of FIG. 2, partly in cross section, taken along line 3-3 of FIG. 4;

FIG. 4 is a cross-sectional view, taken along line 4-4 of FIG.

FIG. 5 is a cross-sectional view of a modified embodiment of a stroke-limiting device according to the present invention with an elastic connection between the stroke-limiting element and the engine unit, taken along line 55 of FIG. 6;

FIG. 6 is a side elevational view of the device of FIG. 5;

FIG. 7 is a partial cross-sectional view of a modified embodiment of the arrangement of FIGS. 5 and 6;

FIG. 8 is a cross-sectional view through a still further modified embodiment of a stroke-limiting device according to the present invention with simultaneous rear support of the engine unit, taken along line 8-8 of FIG. 9; and

FIG. 9 is a cross-sectional view taken along line 9-9 of FIG. 8.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIG. 1, the engine unit generally designated therein by reference numeral 10 which consists of the engine 11, of the clutch housing 12, and of the change speed gear 13, is suspended at the vehicle superstructure in a known manner, not illustrated in detail in FIG. 1, within elastic bearings, for example, by means of two laterally arranged forward rubber bearings and one rearward rubber bearing arranged, for instance, at the rear end of the change speed transmission, in particular in such a manner that the engine unit 10 is able to swing or pivot about a longitudinal axis which is disposed in the vertical longitudinal center plane containing the crankshaft axis. The longitudinal pivot axis can be disposed thereby in the main inertia axis of the drive engine, i.e., can extend through the center of gravity S thereof, either horizontally or at an inclination or also more or less below or above the center of gravity.

According to the present invention, the vertical movement of the drive unit caused in particular by unevenesses of the road surface, is limited in one, two or three points, A, B, C with free movability by the stroke-limiting devices generally designated by reference numerals 14, and 16, respectively. The limitation in the forward point A takes place, for example, at a forward crossbearer 17, the limitation in point B at a rearward crossbearer 18 of a so-called drive stool which is elastically connected with the remainder of the vehicle frame or vehicle body, and the limitation in point C at a frame tubular member 19 which accommodates, for example, the change speed gear 13 and the cardan shaft 20 and is fiangedly conhected to the change speed gear 13.

In general, a stroke limitation in all three points is not necessary. Under certain circumstances, a limitation within the center point B approximately below the center of gravity S suffices. However, a limitation in two points is more appropriate, particularly in the points A and C, possibly also in points A and B or in points B and C or in two other points separated from each other by as large as possible a distance in the longitudinal direction of the engine.

FIGS. 2 to 4 illustrate a stroke-limiting device corresponding approximately to that at point A in FIG. 1. A connecting member 22 of the stroke-limiting device is rigidly secured, for example, by means of bolts 23, by welding or the like at a bearer member 21 of the engine 11. A square or rectangular guide part 25 of the steel core 26 is inserted in a vertical slot 24 of the connecting element 22 so as to be adjustable in the vertical direction. A threaded bolt 27 thereby clamps together the steel core 26 and the connecting member 22 in the adjusted position. The steel core 26 is surrounded by a rubber cushion 28 which is additionally connected adheringly by means of webs 29 with the U-shapedstructural steel members 30-as also appropriately with the 'steel core 26-by vulcanization or the like. The structural steel members 30 are connected by means of bolts 31, by welding or the like with the crossrails 32 and 33 which, together with the structural elements 30 surround the rubber cushion 28 in a framelike manner and, for example, in their turn are threadably secured at the forward driving stool crossbearer 17 or form a part thereof.

The arrangement is thereby so made and the abutment part formed by the steel core 26 and the elastic cushion 28 is thereby so adjusted within the slot 24 that the rubber cushion 28 has by means of its spherical or curved surfaces 34 and 35 in the normal rest position of the vehicle and, of the engine a free play e, and e, which corresponds to the free swinging or deflection path of the drive unit 10 or engine 11 relative to the FIGS. 5 and 6 are again designated with the same numerals. The rubber cushion 28 is provided with protective and reinforcing members 34a, 35a, thereby eliminating premature wearing of the rubber surface by the action of friction on the parts of the crossrails 32, 33.- I 1 In contradistinction to the preceding embodiment, the connection between the rubber cushion 28 andthe engine ll.is realized in this embodiment by a connecting element 220 which is elastically connected with the engine 11. The elastic connection takes place by meansrof two: ring- shaped rubber discs 36 and 37 which are interposed between a metal disc 38 rigidly connected with the upper end of the connecting elevehicle or the respective vehicle part or driving stool part 17. If

the driving unit deflects in the vertical direction either downwardly or upwardly relative to the vehicle, the abutment member 26, 28 after traversing the free deflection path e, or e is pressed by means of the connecting member 22 against the crossrails 32 or 33 effective as counter abutment members, and the rubber or similar elastic material is deformed whereby thelateral webs 29 maintain the connection with the structural parts 30 or with the vehicle part 17 without opposing any significant resistance to the vertical movement of the abutment part 26, 28. After termination of the deflection, the abutment part 26, 28 returns into its noise-insulating center position in which is devoid of any contact due to the play at e, and e In FIGS. 5 and 6, a modified embodiment of the present invention is illustrated, and more particularly, for example, in conjunction with a stroke-limiting arrangement approximately at the place B of FIG. 1. The same parts as those in FIGS. 2 to 4 are again designated with the same reference numerals.

in FIG. 7, a modified embodiment of the arrangement shown in FIGS. 5 and 6 is disclosed. The same parts as those in ment 22a and two further metal discs 39 and 40 without metallic contact thereof whereby the metal discs 39 and 40 at their ends are threadably connected at the engine I] by means of bolts 41. The counterabutrnent part consisting of structural steel elements 30 and of the rails 32 and 33 is secured, for example, by means of bolts 42 at the crossbearer 18 of a driving stool or other vehicle part.

FIGS. 8 and 9 illustrate an embodiment which is particularly suitable for a stroke limitation at the rear end of the drive unit, i.e., at the rear end of the change speed transmission, approximately at the point C.

An approximately trapezoidally shaped, ringlike outer abutment part 45 is secured at a rearwardly extending arm43 of the drive unit or change speed transmission housing by means of a bolt 44; rubber cushions 46 and 47 are secured by vulcanizing at the lower and upper inner surfaces of the outer abutment part 45. Furthermore, an inner abutment part 48 is supported by the outer abutment part 45 by means of lateral rubber webs 49 which are adheringly and securely connected by vulcanization with both the outer as also the inner abutment part. The inner abutment part 48 is adjustable by a crossbolt 50, possibly in the direction of height and is connected by clamping or the like with a U-shaped structural part 51 which, in its turn, is secured at a crossbearer52'in the vehicle frame, of the body or the like by welding or in a similar, known manner.

If so desired, an inverse arrangement may also be provided in such a manner that the inner abutment part 48 is connected with the drive unit and the outer abutment part 45 with the vehicle, for example, with the body frame, driving stool or the like. Furthermore, the abutment device may serve simultaneously or the usual elastic bearing support of the drive unit in the vehicle in that, for example, the outer abutment part 45 connected with the drive unit is supported on the crossbearer 52 or the like by means of obliquely arranged rubber cushions 53 in such a manner that the abutment part 45 or the drive unit is able to pivot under the engine torque about a longitudinal axis extending through the point P. By reason of the free deflection path e, and e; between the inner and the outer abutment part and by reason of the yieldingness of the web elements 49 offering slight resistance, these rotary movements are permitted without difficulty whereas vertical movements between the two abutments parts or between the drive unit and the vehicle are limited after traversing the free deflection path e, or e 98 2 by the elastic abutments of the rubber cushions 46 or 47.

While we have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art, and we therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

I claim:

1. An arrangement in a vehicle for the stroke limitation of an elastically suspended drive unit having a longitudinal pivot axis, comprising:

a plurality of elastic abutment means operatively associated between the drive unit and the vehicle, and located at a distance with respect to the longitudinal pivot axis;

said elastic abutment means being located at least approximately in a vertical longitudinal plane of the drive unit so as to provide relative movement in the vertical direction in case of vertical impacts and relative movement in an approximately horizontal direction in case of rotary oscillations about the longitudinal pivotaxis; said elastic abutment means having alimited free deflection path between the drive unit and the vehicle;

means for mounting said elastic abutment means with respect to the drive unit and the vehicle; whereby said elastic abutment means comes into abutment in a vertical direction after the'limited free deflection path; and t at most, only approximately minor abutment occurs between said elastic abutment means in the case of rotary oscillations about the longitudinal pivot axis under the effect of engine torque.

2. An arrangement according -to claim 1, wherein each elastic abutment means is arranged above the center of gravity point of the drive unit.

3. An arrangement according to claim 1, wherein each elastic abutment means is arranged below the center of gravity point of the drive unit.

4. An arrangement according to claim 1, wherein said elastic abutment means are arranged in the forward and rear end area of the drive unit.

5. An arrangement according-to claim 1, wherein said elastic abutment means are arranged in one of the forward and rear end areas and in a zone of a vertical transverse plane of the drive unit, said plane extending substantially within the area of the center of gravity of the drive unit.

6. An arrangement according to claim 1, wherein the free deflection path of the drive unit relative to the vehicle is larger in the downward direction than in the upward direction.

7. An arrangement according to claim-l, wherein the elastic abutment means are adjustable.

8. An arrangement according to claim 1, wherein the free deflection paths are adjustable.

9. An arrangement'having at least two parts to be mutually supported in a limited manner according to claim 1, wherein said mounting means includes at least one freely adjustable abutment part which is operatively connected in the vertical direction substantially without play with one of the two parts to be supported in a limited manner and is operatively connected with the other of the parts-by elastic means offering slight resistance in the vertical direction, and wherein said other part includes counterabutment means against which the first-mentioned abutment part abuts after traversing the free deflection path.

10. An arrangement according to claim9, further comprising connecting means for connecting said abutment part with said one of the two parts to provide the play-free connection in the vertical direction.

11. An arrangement according to claim 10, wherein said connecting means is rigidly connected with said one part.

12. An arrangement according to claim 10, wherein said connecting means is connected with said one part with slight yieldingness.

13. An arrangement according to claim 12, wherein said connecting means provides a yieldingness in all directions.

14. An arrangement according to claim 10, wherein the connection between said connecting means with the abutment part is vertically adjustable and the vertical adjustment is obtained by means of an elongated aperture and clamping bolt means. 1

15. An arrangement according to claim 9, wherein the abutment part is connected with the part, which is to be supported with a free deflection path relative thereto in the vertical direction, by elastic web means offering relatively slight resistance in the vertical direction.

16. An arrangement according to claim 1, wherein the elastic abutment means is connected with the part, which is to be supaported with a free deflection path relative thereto in the vertic direction, by elastic web means offering relatively slight resistance in the vertical direction.

17. An arrangement according to claim 16, wherein the elastic abutment means are provided with a layer of synthetic resinous material.

18. An arrangement according to claim 16, wherein said elastic web means extends substantially horizontally toward the part.

19. An arrangement according to claim 1, wherein at least one rubber cushion means provided with rigidly metallic core means is provided as abutment part carrying the elastic abutslight resistance in the vertical direction, wherein said other part includes an outer abutment part substantially surrounding said inner abutment part, said outer abutment part being provided with said elastic abutment means against which the inner abutment part abuts after traversing the free deflection path.

22. An arrangement in a vehicle for the stroke limitation of an elastically suspended drive unit having a longitudinal axis, wherein the improvement comprises elastic abutment means operatively associated between thedrive unit and the vehicle, and further means for mounting said elastic abutment means at least approximately in a vertical longitudinal center plane of the drive unit so that said elastic abutment means comes into abutment in a vertical direction after a limited free deflection path whereas normally no abutment occurs between said abutment means in the direction of rotation about the longitudinal axis of the drive unit under the effect of the engine torque, said further means includes at least one freely adjustable abutment part which is operatively connected in the vertical direction substantially without play with one of the two parts to be supported in a limited manner and is operatively connected with the other of the parts by elastic means offering slight resistance in the vertical direction, said other part includes counterabutment means against which the first-mentioned abutment part abuts after traversing the free deflection path, wherein the abutment part is connected with the part, which is to be supported with a free deflection path relative thereto in the vertical direction, by elastic web means offering relatively slight resistance in the vertical direction.

23. An arrangement according to claim 22, wherein the other abutment part having a free deflection path to the one abutment part is connected with the associated part to be supported by the interposition of elastic means.

24. An arrangement according to claim 23, wherein the interconnected elastic means serve simultaneously for the elastic support of the drive unit at the vehicle frame.

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