US3759236A

US3759236A - Centrifugal governor for regulating the rpm of internal combustion engines

Info

Publication number: US3759236A
Application number: US00186194A
Authority: US
Inventors: H Staudt; E Ritter
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1970-10-03
Filing date: 1971-10-04
Publication date: 1973-09-18
Anticipated expiration: 1990-09-18
Also published as: FR2109877A5; DE2048635B2; DE2048635C3; GB1300708A; AT309148B; DE2048635A1

Abstract

In a centrifugal governor for regulating the rpm of an internal combustion engine, there is provided a governor member which, through a linkage system, controls the position of the fuel quantity control rod of a fuel injection pump. The rpm regulator includes a main regulator spring which opposes the displacing force of the governor member and the tension of which is variable by an arbitrarily settable operator lever for determining the engine rpm. The rpm regulator further includes an additional idling spring affecting the motion of the governor member during an arbitrarily variable portion of the travelling path of the governor member. The length of said portion is changed as a function of the position assumed by said operator lever.

Description

United States Patent Staudt et al.

{ 1 Sept. 18, 1973 CENTRIFUGAL GOVERNOR FOR REGULATING THE RPM OF INTERNAL COMBUSTION ENGINES [75] Inventors: Heinrich Staudt,

Markgroningen-Talhausen; Ernst Ritter, Stuttgart, both of Germany [73] Assignee: Robert Bosch Gmbil, Stuttgart,

Germany [22] Filed: Oct. 4, 1971 [21] Appl. No.: 186,194

[30] Foreign Application Priority Data Oct. 3, 1970 Germany P 20 48 635.5

[52] U.S. Cl. 123/140 R; 123/140 J, 123/139 R [51] Int. Cl. F026 1/04 [58] Field of Search 123/140 R, 140 MC, 123/140 MP, 140 J, 139

[56] References Cited UNITED STATES PATENTS 2,241,096 5/1941 McCullough 123/140 R 2,259,693 10/1941 Hogeman 123/140 R 3,358,664 12/1967 Thompson 123/139 R 3,398,729 8/1968 Maddalozzo 123/139 AP Primary Examiner-Laurence M. Goodridge Assistant Examiner-Cort Flint Att0rney-Edwin E. Greigg [5 7] ABSTRACT In a centrifugal governor for regulating the rpm of an internal combustion engine, there is provided a governor member which, through a linkage system, controls the position of the fuel quantity control rod of a fuel injection pump. The rpm regulator includes a main regulator spring which opposes the displacing force of the QYE QQt new??? an the n n f wis is variable by an arbitrarily settable operator lever for determining the engine rpm. The rpm regulator further includes an additional idling spring affecting the motion of the governor member during an arbitrarily variable portion of the travelling path of the governor member. The length of said portion is changed as a function of the position assumed by said operator lever.

3 Claims, 4 Drawing Figures PATENTEU EPW B v 3,759,236

SHEEI 1 OF 3 PATENTED SEPI 81973 3, 753 2 36 SHEET 3 If 3 CENTRIFUGAL GOVERNOR FOR REGULATING THE RPM OF INTERNAL COMBUSTION ENGINES BACKGROUND OF THE INVENTION This invention relates to a centrifugal governor for regulating the rpm of internal combustion engines and is of the type that has a governor member moved in an rpm-dependent manner and connected through at least one intermediate lever with the fuel quantity control member of a fuel injection pump. The centrifugal rpm regulator is further of the type in which the effect of the resetting force of at least one regulator spring is arbitrarily variable by means of an operator lever for setting the desired rpm and wherein said resetting or return force affecting the governor member is amplified in the idling range by the force of an additional return spring which, with one end, bears against the inner wall of the regulator housing.

In known rpm regulators of the aforenoted type (such as disclosed, for example, in German Pat. Nos. 1,011,223 and 1,080,814), by means of the additional return spring a quiet and stable idling of the internal combustion engine is achieved.

The aforenoted additional return spring is always effective (i.e. exerts a force on the governor member) along a predetermined portion of the entire travelling path of the governor member, irrespective of whether the regulator is set to regulate idling rpms or load rpms. Consequently, the aforenoted additional return spring always becomes effective or ineffective for the same position of the governor member and the fuel quantity control member of the fuel injection pump.

Thus, if the regulator is set by means of the operator lever, to a certain load rpm and the load is entirely or substantially entirely removed from the internal corn bustion engine (zero load run), then, as the governor member covers the aforenoted predetermined portion of its travelling path, the additional return springbecomes effective, so that the degree of proportionality (hereinafter referred to as P-degree) of the regulator is increased to an extent proportional to the stiffness of the additional return spring. Such a phenomenon,.however, is undesirable particularly in case of rpm regulators associated with AC current generating aggregates, since the rpm thereof has to be maintained within narrow limits due to frequency considerations.

The same disadvantage appears if such a regulator is designed for at least two load rpm's, wherein the lower rpm lies close to or within the operating range of the additional spring.

In addition to the aforenoted examples of application, the known arrangement of the additional return spring has particularly a disadvantageous effect if the rpm regulator is used in supercharged engines. In such a case an increased full load fuel quantity is set at the fuel injection pump as a function of the charging pressure but independently of the rpm by means ofa particular control device, while simultaneously, however, the operational range of the additional return spring is raised in the direction of increased fuel delivery. Consequently, in a zero load run the new increased P- degree caused by the additional spring will set in even earlier and in a more pronounced manner.

In other known rpm regulators, as disclosed for example in German Pat. No. 958,704, the idling range is narrowed by rendering ineffective in the load range an intermediate spring cooperating with the additional return spring. The effect of the additional return spring is not entirely eliminated, but merely limited to a portion of the idling range. Such limitation of the effect of the additional idling spring is, however, insufficient particularly in case of supercharged engines.

in rpm regulators of the type having contrary to the regulators described so far permanently set return springs (such as disclosed in German Pat. No. 838,380), it is known to arrange an additional return spring in such a manner that the latter becomes activated only in the idling setting of the operator lever, but not in the load setting, so that a large P-degree is achieved for idling run and a small P-degree for load run.

OBJECT AND SUMMARY OF THE INVENTION It is an object of the invention to achieve the effect set forth in the preceding paragraph even in rpm regulators in which the return force of the regulator spring is changeable in an arbitrary manner by means of an operator lever for the setting of the desired rpm and wherein the effect of the additional return spring can be entirely eliminated in the load range.

Briefly stated, according to the invention, the effect of the force of the additional return spring is variable as a function of the position of the operator lever.

The invention will be better understood as well as further objects and advantages become more apparent from the ensuing detailed specification of a preferred although exemplary embodiment of the invention taken in conjunction with the drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a sectional view (taken along line [-1 of FIG. 2) of the preferred embodiment of the invention;

FIG. 2 is a sectional view taken along line 1l-ll of FIG. 1;

FIG. 3 is a sectional view taken along line III-III of FIG. 1 and FIG. 4 is a diagram illustrating control curves characterizing the regulator according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Turning now to FIG. I, to a cam shaft 10 of a fuel injection pump for an internal combustion engine (neither shown) there is affixed a carrier member 11 on which there are swingably mounted centrifugal weights 12. The latter have arms 13 which engage a frontal face 14 of a governor member 15 which, at its end oriented towards the cam shaft 10, is provided with an internal circumferential rib 16. During the travel of the governor member 15, the rib 16 is guided on a narrow annular zone of a cylindrical portion 17 of the carrier member 1 I in an axial alignment with the regulator axis. The governor member 15 is formed substantially of two components: a governor sleeve 15a which has the aforenoted internal circumferential rib l6 and a link 15b which is connected with the governor sleeve 15a through a force-transmitting roller bearing assembly 18. As best shown in FIG. 2, the link 15b has two pins 19 which are inserted in the lower terminus 20 of a guide lever 21 which, in turn, is pivotally secured to a pin 22. The latter, as best shown in FIG. 2, is affixed to the two-part regulator housing 23.

The guide level 21 is formed of two parallel arranged plate members which, for constituting a single lever,

are interconnected by a spacer member 24 having two oppositely directed terminal pins 25. As well seen in FIG. 2, the left pin 25 engages an intermediate lever 26 which, in turn, with its forked terminus 26a projects into a recess 27 in the regulator housing 23 and is supported on a pin 29. The latter traverses the recess 27 as well as a symmetrically arranged similar recess 28. The intermediate lever 26 is connected by means of a link 30 with a fuel quantity control rod 31 associated with the fuel injection pump. The fuel quantity control rod 31 is disposed, as shown in FIG. 1 and as indicated with dash-dot lines in FIG. 2, to the left of the vertical median plane of the regulator. In cases of structural arrangements where the fuel quantity control rod is situated to the right of the aforenoted plane as shown in FIG. 2 at 31a, the intermediate lever 26, with its forked end 26a may be inserted into the recess 28 and connected with the terminal pin 25 which is situated to the right of the spacer member 24. in the regulator housing 23 there is situated a swinger lever 32 pivotally held by pins 33. To one of the latter there is secured an operator lever 34 which is disposed externally of the regulator housing 23 and which is shown in one of its extreme positions. To the swinger lever 32 there is pivotally secured at tensioning rocker 35 into which there is hooked one end of a regulator spring 36. The other end of the regulator spring 36 is hooked into an eye 37 provided in an attachment 38 of a power lever 39. The latter is supported by the same pin 22 which is associated with the guide lever 21 and serves for the transmission ofthe force ofthe governor member 15 to the regulator spring 36 and conversely. The position of the tensioning rocker 35 and thus the tension of the regulator spring 36 may be adjusted by means of a setscrew 40.

In the illustrated position of the swinger lever 32 the regulator spring 36 is in its maximum tensioned condition and thus the regulator is set to the highest rpm. At the same time, the lower terminus of the power lever 39 abuts against a head 41 of a stop screw 42 which is threadedly engaged in a boss d3 of the regulator housing 23 in an adjustable manner and which is secured in its position by means of a nut 44. The power lever 39 has, close to its lower terminus, an engagement face 45 through which the link 13b, with its arcuate frontal face 46, transmits to the power lever 39 the moving force of the governor member 15.

To the intermediate lever 26 there is attached one end of a weak auxiliary spring 48 which functions as a starting and play-equalizing spring. The other end of the aforenoted spring is secured to a pin 49 affixed to the regulator housing 23.

The swinger lever 32 is provided at a web-like portion 50 thereof with a pin 53 which is engaged by one terminus 52 ofa drag spring 53 (see FIGS. 2 and 3), the other terminus 54 of which is hooked into one arm of a two-arm lever 55. The lever 55 is supported in a bearing bracket 56 affixed to the regulator housing 23 and projects with a nose 57 of its other lever arrn into a slot 58 of a spring-loaded sleeve 59 (see FIGS. 1 and 3). The latter forms one part of a resilient idling abutment generally indicated at 60 which is threadedly engaged in the wall of the regulator housing 23 and which has, besides an additional return spring 61 (referred to hereinafter as additional idting spring) and the springloaded sleeve 59, an adjustable spring seat disc 62 which is immobilized in its set position by means of a nut 63.

The drag spring 53 is tensioned in the shown position of the swinger lever 32, and has shifted through the lever 55 the spring-loaded sleeve 59 into its position illustrated in FIGS. 1 and 3, so that the latter is moved out of the path of travel of the intermediate lever 26. If the operator lever 34 is moved from its shown, maximum rpm position into a lower rpm position, that is, into a position which corresponds to the dash-dotted position 36 of the regulator spring or into an idling rpm position, then the drag spring 53 has no bias and therefore the lever 55 and the spring sleeve 59 are in their dash-dotted position shown in FIG. 3 in which the spring-loaded sleeve 59 is adapted to abut the intermediatelever 26 in the course of the travel of the latter.

Turning now to FIG. 4, there are shown several regulator curves characterizing the regulator according to the invention. In the ordinate there is shown the travelled distance R of the fuel quantity control rod 31, whereas the abscissa indicates the rpm n. During the starting of the internal combustion engine and in a maximum setting position of the operator lever 34, the regulator follows the bold-face curve A-B-C-D-E. Up to the rpm n (from A-B) the fuel quantity control rod 31 remains in its starting position R As the rpm n is exceeded, the governor member l5 travels a distance a against the force of the starting spring 48 (FIG. 1) and thus the rod 31 reaches at an rpm n, in point C the full load position R,,. This position is maintained by the fuel quantity control rod 31 in the present example up to the point D and an rpm n Upon a further increase in the rpm beyond in, the regulator decreases the rpm until the fuel control rod 31 reaches in the extreme case the position R in point E at 11 In the idling position of the operator lever 34, the regulator operates in accordance with the bold-face curve A-B-C-F-G and in a setting of the operator lever for the regulation of an rpm which is between the idling rpm in and the rpm n additionally to the starting range A-B-C, the thinline curves H, J or X will be followed. The kink in the curve C-F-G in point F is caused by the activation of the additional idling spring 61. The aforedescribed sequence of occurrences would take place in case of a permanently installed idler spring for all rpms to be regulated in a fuel quantity control rod position R which is indicated by the thin broken line L and, in case of a down-regulation from an rpm n,,, it would lead to an rpm increase from m, to n By virtue of the deactivation of the effect of the additional idling spring 61 according to the invention (See FIGS. l and 3), the spring activation point runs in the upper rpm range from the point M downward along the dash-dotted line N so that in the regulator according to the invention no rpm increase beyond it is possible.

The aforenoted effect is important particularly when the regulator is used in supercharged engines and has a charging pressure-dependent control device (not shown) by means of which both the full load regulator travel R, and the regulator travel R, for the activation of the additional idling spring 61 are raised to R, and R respectively. In such a case, in a maximum position of the operator lever, the regulator would work along the line A-B-C -D E, (boldface broken line portion) and in case of a non-deactivated idling spring, the down-regulation from the highest rpm n, on, would follow under R the dotted line P and the rpm would increase up to 7:

In case of rpm changes in the internal combustion engine, the centrifugal weights 12 change their'position and cause thereby a shift in the governor member 15 in cooperation with the regulator spring 36. The governor sleeve 15a thus slides with its inner circumferential rib 16 axially on the carrier portion 17 while the link 15b, pivotally attached to the guide lever 21, moves approximately in the direction of the axis of the cam shaft about the pivotal axis 22 of the guide lever 21. If the rpm of the internal combustion engine increases because of a drop in the load, then the centrifugal weights l2 shift the governor member towards the right against the force of the return spring 36. At the same time, the fuel quantity control rod 31 is also moved towards the right resulting in a continuously decreasing fuel delivery to the internal combustion engine until, corresponding to the degree of proportionality (P- degree) of the regulator, at a higher rpm a new condition of equilibrium sets in. The same occurrences takes place in a reverse direction when the load on the internal combustion engine increases.

In the description that follows, there will be discussed in further detail the mode of operation of the regulator according to the invention taking into account different operational conditions, whereby operational points on the curves illustrated in FIG. 4 will be referred to.

In the shown position of the swinger lever 32, that is, in a maximum position of the operator lever 34 when the engine is at a standstill and in the range of the very low rpm It -n which appear during the starting of the internal combustion engine, the centrifugal weights 12 assume the shown closed position. At the same time, the governor member 15, under the effect of the starting spring 48, maintains the guide lever 21 and through the intermediate lever 26 the fuel quantity control rod 31 in a position R, In this position the fuel injection pump of the internal combustion engine delivers a fuel quantity which is in excess of the full load fuel quantity and which facilitates the starting of the internal combustion engine. As soon as the engine is running, the centrifugal force exerted on, and transmitted by the weights 12 overcomes the force of the spring 48 and moves the governor member 15 through a distance a until it abuts the engagement face'45 of the power lever 39. In this position of the governor member 15 the fuel quantity control rod 31 is in its full load position R, and thus a full load fuel quantity is delivered to the internal combustion engine.

At an rpm beyond n, the force of the centrifugal weights 12 also overcomes the force of the regulator spring 36 and thus the governor member 15 is shifted even further to the right. At the same time the guide lever 21 together with the power lever 39 is pivotally moved and through the intermediate lever 26 the fuel quantity control rod 31 of the fuel injection pump is displaced even further towards stop" (R,,) until finally, because of the decrease ofthe fuel quantity delivered to the internal combustion engine, a new condition of equilibrium sets in and the rpm of the internal combustion engine does not increase any further. In the extreme case the regulator shuts off fuel delivery at n, (R,,). In this operational range of the regulator the intermediate lever 26 does not come into contact with the spring-loaded sleeve 59, so that the resilient idling abutment 60 is not activated. This contributes to the fact that the rpm 11,, appearing during down-regulation is not exceeded. The P-degree of the regulator according to the invention is thus lower than ifthc force of the additional return spring 61 is added to those of

springs

36 and 48 as it is the case in known regulators in which the additional idling spring 61 is permanently set and is activated also in the upper rpm range. In such a case the rpm would increase to n If the swinger lever 32 is brought into a position in which the regulator spring 36 assumes a position shown in FIG. 1 in dash-dotted lines at 36', then the centrifugal weights 12 overcome the tension of the

springs

36 and 48 even earlier and the regulator regulates a low rpm corresponding to the curves H, .l and K.

If the swinger lever 32 is pivoted even further in a clockwise direction by rotating the operator lever 34, for example, for an idling rpm setting of the internal combustion engine (curve A-B-C-F-G), the centrifugal weights 12 overcome the force of the

springs

36 and 48 as early as at the low rpm n In this case the centrifugal weights 12 shift the governor member 15 to such an extent that the intermediate lever 26, for a position R, of the fuel quantity control rod 31, arrives in the operational range of the additional idling spring 61 of the idling abutment 60. The purpose of spring 61 is to dampen possible oscillations of the regulator in order to ensure a quiet, smooth idling. The length of the regulator spring 36 may be selected in such a manner that in the idling range C-F-G it does not become effective at all. One terminus of the spring 36 then hangs loosely in the eye 37. In this case only the springs 48 and 6] supply the return force (see C-F-G). The spring 48 further serves to equalize the play in the articulation between the governor member 15 and the fuel quantity control rod 31.

In the two last-described operational ranges, that is, at low or idling rpms, the additional idling spring 61 becomes partially effective (curves J and K) or, as shown in FIG. 3 by the dash-dotted position of the spring-loaded sleeve 59, it becomes fully operational (curves C-F-G and H).

By changing the bias of the spring 61 by means of the spring seat disc 62 or by means of replacing the spring 61 with a spring which has a different length or stiffness as well as by means of replacing the drag spring 53, the effective range of the idling abutment may be coordinated in a desired manner with the required regulator characteristics. Stated differently, the dash-dotted curve N (FIG. 4) may be shifted towards the left or the right or may be changed in its slope.

What is claimed is:

1. In a centrifugal-type rpm regulator connected to the fuel quantity control member of a fuel injection pump associated with an internal combustion engine, the improvement comprising,

A. a governor member,

B. means for displacing said governor member as a function of the engine rpm.

C. a first lever means connecting said governor memher with said fuel quantity control member, said first lever means having a path of travel through which it is displaced by said governor member,

D. a regulator spring connected to said first lever means for opposing the force exerted on said governor member by the means defined in (B),

E. an additional idling spring means for opposing during the starting and idling rpms the force exerted on said governor member by the means defined in (B), said additional idling spring means having one end thereof located within a housing within which said governor member is mounted,

F. an arbitrarily settable operator lever connected to said regulator spring for varying the bias thereof and G. a second lever means connecting said arbitrarily settable operator lever to said additional idling spring means for varying the moment of activation thereof with respect to the position of said governor member as a function of the position of said operator lever,

said additional idling spring means being movable by said second lever means into and out of said path of travel,

said operator lever in its positions beyond the idling setting arranged to de-activate at least partially said additional idling spring means.

2. An improvement as defined in claim 1, wherein said additional idling spring means, when positioned in said path of travel arrives in abutment with said first lever means after a predetermined travel thereof dependent upon the position of said additional idling spring means; said additional idling spring means, when positioned beyond said path of travel, remains ineffective for the entire displacement of said first lever means,

3. In a centrifugal-type rpm regulator connected to the fuel quantity control member of a fuel injection pump associated with an internal combustion engine, the improvement comprising,

A. a governor member,

B. means for displacing said governor member as a function of the engine rpm,

C. a first lever means connecting said governor mem' her with said fuel quantity control member,

E. an additional idling spring means for opposing during the starting and idling rpms the force exerted on said governor member by the means defined in F. an arbitrarily settable operator lever connected to said regulator spring for varying the bias thereof and G. a second lever means connecting said arbitrarily settable operator lever to said additional idling spring means for varying the moment of activation thereof with respect to the position of said governor member as a function of the position of said operator lever, said second lever means including:

a. a swinger lever the position of which is determined by said arbitrarily settable operator lever,

b. a pivotally held lever having an end in engagement with said additional idling spring means for shifting the same and c. a drag spring having one end connected to said swinger lever and another end connected to said pivotally held lever; said arbitrarily settable operator lever determines the position of said additional idling spring means through said swinger lever, said drag spring and said pivotally held lever.

Claims

1. In a centrifugal-type rpm regulator connected to the fuel quantity control member of a fuel injection pump associated with an internal combustion engine, the improvement comprising, A. a governor member, B. means for displacing said governor member as a function of the engine rpm, C. a first lever means connecting said governor member with said fuel quantity control member, said first lever means having a path of travel through which it is displaced by said governor member, D. a regulator spring connected to said first lever means for opposing the force exerted on said governor member by the means defined in (B), E. an additional idling spring means for opposing during the starting and idling rpm''s the force exerted on said governor member by the means defined in (B), said additional idling spring means having one end thereof located within a housing within which said governor member is mounted, F. an arbitrarily settable operator lever connected to said regulator spring for varying the bias thereof and G. a second lever means connecting said arbitrarily settable operator lever to said additional idling spring means for varying the moment of activation thereof with respect to the position of said governor member as a function of the position of said operator lever, said additional idling spring means being movable by said second lever means into and out of said path of travel, said operator lever in its positions beyond the idling setting arranged to de-activate at least partially said additional idling spring means.

2. An improvement as defined in claim 1, wherein said additional idling spring means, when positioned in said path of travel arrives in abutment with said first lever means after a predetermined travel thereof dependent upon the position of said additional idling spring means; said additional idling spring means, when positioned beyond said path of travel, remains ineffectIve for the entire displacement of said first lever means.

3. In a centrifugal-type rpm regulator connected to the fuel quantity control member of a fuel injection pump associated with an internal combustion engine, the improvement comprising, A. a governor member, B. means for displacing said governor member as a function of the engine rpm, C. a first lever means connecting said governor member with said fuel quantity control member, D. a regulator spring connected to said first lever means for opposing the force exerted on said governor member by the means defined in (B), E. an additional idling spring means for opposing during the starting and idling rpm''s the force exerted on said governor member by the means defined in (B), F. an arbitrarily settable operator lever connected to said regulator spring for varying the bias thereof and G. a second lever means connecting said arbitrarily settable operator lever to said additional idling spring means for varying the moment of activation thereof with respect to the position of said governor member as a function of the position of said operator lever, said second lever means including: a. a swinger lever the position of which is determined by said arbitrarily settable operator lever, b. a pivotally held lever having an end in engagement with said additional idling spring means for shifting the same and c. a drag spring having one end connected to said swinger lever and another end connected to said pivotally held lever; said arbitrarily settable operator lever determines the position of said additional idling spring means through said swinger lever, said drag spring and said pivotally held lever.