US3530845A

US3530845A - Centrifugal governor for controlling the r.p.m. of diesel engines

Info

Publication number: US3530845A
Application number: US773619A
Authority: US
Inventors: Heinrich Staudt; Rolf Muller; Eberhard Hofmann
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1967-11-14
Filing date: 1968-11-05
Publication date: 1970-09-29
Anticipated expiration: 1987-09-29
Also published as: BG16353A3; JPS5022167B1; FR1585720A; AT288088B; ES360231A1; GB1245145A

Description

United States Patent [72] Inventors Heinrich Staudt,

Markgroningen Weilertalhausen; H H Rolf IVIiilIer, Stuttgart-Zuffenhausen; Eberhard Hofmann, Kirchberg, Murr- Neuhof, Germany [21] Appl. No. 773,619

[22] Filed Nov. 5, 1968 [45] Patented Sept. 29, 1970 [73] Assignee Robert Bosch GmbH,

Stuttgart, Germany [32] Priority Nov. 14, 1967 [33] Germany [54] CENTRIFUGAL GOVERNOR FOR CONTROLLING THE RPM OF DIESEL ENGINES [50] Field ofSearch 123/32, 119, 139, 140; 74/526 [56] References Cited UNITED STATES PATENTS 2,818,053 12/1957 Shallenberg 123/140 3,130,599 4/1964 Haasm, 74/526 Primary Examiner Laurence M. Goodridge Attorney-Edwin E. Greigg ABSTRACT: In a diesel engine, a centrifugal governor is connected (1 by a first linkage means to the control rod ofa fuel injection pump to cause displacement of said rod thereby varying the fuel delivery and (2) by a second linkage means to an adjustable abutment which limits said displacement and 7 Claims 1 Drawing thus limits the maximum fuel delivery under various operating [52] U.S.Cl... 123/140 conditions. The position of said adjustable abutment is inde- [51] Int.Cl F02d 1/04 pendentofthe position ofsaid firstlinkage means.

43 34b 30 i 340 2/ e 36 34/1 34 29 42" E I l ('1 I 29a I I 4 42a '5: 346 4 1 38b 25 28 i '1 5 O I- I A,

l 4:7, I 16 39 3% i 40 20a 3 l I I s' 330 9 I 4E s p 9 j {a I p:

I LC a 22 2 l, 7 1/1, I 6 230 a ,5

. 4 Patented Sept. 29, 1970 3 5 8 5 VIII! lNVf/VTORS h'l'm'l'ch STAUDT Eberhard l/OFHAN/V Rolf MIJZIER CENTRIFUGAL GOVERNOR FOR CONTROLLING THE RPM OF DIESEL ENGINES BACKGROUND OF THE INVENTION The invention relates to a centrifugal governor for controlling the r.p.m. of diesel engines by means of a connecting linkage which, on the one hand, is in engagement with the regulator member displaced by the governor weights as a function of the rpm. and, on the other hand, is connected with the fuel delivery control rod of the injection pump. The displacement of the fuel delivery control rod is, in the direction of increasing fuel quantities, limited by an adjustable stop determining a maximum fuel delivery. An accumulator (a spring-type storage device) is loaded as soon and as long as the said connecting linkage tends to displace the said fuel delivery control rod beyond said stop or abutment.

Various centrifugal governors of the above outlined structure have already been known. Such devices are described, for example, in German Pat. No. l,0l0,32l and U.S. Pat. No. 2,259,693.

In these centrifugal governors the adjustable stop is coupled with said connecting linkage and is therefore affected by the position thereof. Stated in other terms, the adjustable stop is shifted with respect to a cooperating abutment plate fixedly secured to the housing and provided with various abutment faces every time the connecting linkage moves.

OBJECT AND SUMMARY OF THE INVENTION It is an object of the invention to provide an improved centrifugal governor arranged in such a manner that the adjustable abutment determining the maximum fuel delivery, is not attached to the connecting linkage and is, consequently, not

affected by the position thereof. The position of the adjustable stop is thus dependent exclusively on the position of the centrifugal weights.

:In order to achieve the aforenoted object, according to the invention, between the centrifugal weights and the regulator member displaceable thereby, there is inserted a transfer element shiftable by the centrifugal weights and coupled with an I DESCRIPTION OF THE PREFERRED EMBODIMENT To the drive shaft 1 ofa fuel injection pump (not shown) for diesel engines there is secured a face plate 2 on which there are pivotally mounted centrifugal weights 3. The radially inwardly extending arms 4 of the weights 3 engage the frontal face 5a of a roller bearing 5 which is slidably mounted on a stub 1a of the drive shaft 1. The roller bearing 5 transmits the displacing forces of the centrifugal weights 3 to a transfer element or adaptor sleeve 6 also slidably mounted on the stub shaft la. The adaptor sleeve 6 receives in a coaxial annular cavity an adaptor spring 7 transmitting the adjusting forces from the adaptor sleeve 6 to the regulator member 8, as will be described in greater detail later. To opposed sides of the regulator member 8 there are fixedly secured in axial alignment pins 9 and 10 which, respectively, are slidably held in axial bore lb of stub la and in axial bore 11b ofa spring seat base 11. The spring seat base 11, in turn, is axially displaceahly held in a socket 12 which threadedly engages a base plate 13 forming part of a housing 13a shown only in broken lines. Within socket 12 there is disposed a control spring 14 which engages, on the one hand, the spring seat base 11 and,

on the other hand, a spring seat disc 15 threadedly held in the socket 12. Through the spring seat disc 15 there passes an axial adjusting screw 16 which, in turn, serves as a seat for an idling spring 17. At its other end, the spring 17 engages the terminal face of pin 10. As a connecting linkage between the regulator member 8 and a fuel delivery control rod 18 of the fuel injection pump, there is provided a shift lever 19, a regulator lever 20, and a guide rod 21, which latter carries a spring-type accumulator generally indicated at 30. The shift lever 19 has a pin 22 by which it is held in a forked extension 23a of a radial bolt 23 extending through and secured to the regulator member 8. The shift lever 19 is pivotally secured to a bearing pin 24 fixedly held in housing 13a and is articulatedly connected to one end of regulator lever 20. A pin 25 secured to an adjusting link 26 extends into a guiding slot 20a of the regulator lever 20. The adjusting link 26 is, in a bell-crank manner, connected through a shaft 27 secured to housing 13a with an externally operable adjusting lever 28 disposed outside of the housing 13a, The guide rod 21 which is pivotally connected to the regualtor lever 20 transmits the adjusting movements of the latter through a spring-type accumulator 30 to an arm 29 rigidly affixed to the control rod 18. If the control rod 18 abuts against a stop during its displacement in either direction and if, thereupon, the guide rod 20 continues its adjusting motion in the same direction, the spring 31 of the accumulator 30 is compressed from one or the other direction.

For stopping the control rod 18 in the direction of full load, there is provided a contour plate 34, the curved edge of which is adapted to be engaged by a finger 29a secured to and protruding from the arm 29. Said edge, as will be seen later, is formed of two consecutive curve-portions: one is associated with additional fuel delivery for starting while the other is an adaptor-curve assisting in the control of fuel subsequent to the starting phase of the engine. The contour plate 34 is provided with a guiding slot 34a into which extends a cam 35 mounted on an eccentric 36 which, in turn, is affixed to the end face of a shaft 37 rotatably held in housing 13a. When shaft 37 is turned, the position of eccentric 36 changes. The contour plate 34 is slidable with respect to cam 35 and substantially parallel to arm 29. For displacing the contour plate 34 dependently of the adaptor sleeve 6, but independently of the motion of regulator member 8, there are provided two

levers

38 and 39 both pivotally attached to a common pin 40 fixedly secured to the housing 13a. The lever 38 pivotally engages with a forked end 38a a pin 6b affixed to a lug 6a which, in turn, is secured to the adaptor sleeve 6. With its end remote from the forked end 38a, the lever 38 transmits the adjusting motion of the adaptor sleeve 6 to lever 39 through the interposed drag spring 41 which, on the one hand, engages an angularly offstanding extension 38b of the lever 38 and, on the other hand, contacts a spring seat 39a affixed to lever 39. The spring seat 39a has a curved extension 39b which is adapted to engage the lever 38 and thus limits the pivotal motion of the lever 39 with respect to pin 40. The lever 39 is held in a forked terminus 42a of a connecting bolt 42 which, in turn, is slidably held in two aligned openings provided, respectively, in spaced flanges 34b and 340 extending normal to the contour plate 34. The connecting bolt 42 is adjustable with respect to the contour plate 34, in a direction parallel to the length dimension of guiding slot 34a, by means of a nut 43 threadedly engaging the connecting bolt 42 and lying against the upper face of flange 34b of the contour plate 34. Between the spring seat 44 secured to the shaft of the connecting bolt 42 and the lower face of flange 3417 there is compressed a coil spring 45 surrounding the connecting bolt 42. A purpose of providing

levers

38 and 39 in the linkage that couples the adaptor sleeve 6 with the contour plate 34 is to obtain, at terminus 42a, a displacement that is larger than that of adaptor sleeve 6.

OPERATION OF THE PREFERRED EMBODIMENT The movable parts of the centrifugal regulator are shown in the position which they assume when the engine is stationary and the externally operable adjusting lever 28 is in its shut-off position.

For starting the engine, the driver moves the externally operable adjusting lever 28, and thus, the adjusting link 26, the control lever 20, the guide rod 21, the arm 29 and control rod 18 are displaced from the inoperative position shown in the figure into the full load position, whereby finger 29a is brought into contact with curve-portion 34' which determines the upper limit of the fuel delivery for start.

After the start of the engine, first the outwardly swinging centrifugal weights 3 shift the adaptor sleeve 6 and the regulator member 8 to the right. The latter is displaced directly by the adaptor spring 7 without compression thereof. Due to the said displacement of regulator member 8, the idling spring 17 is continuously and increasingly compressed by the pin 10 until the regulator member 8 abuts against the outer terminal face of spring seat base 11. As the adaptor sleeve 6 moves to the right, it causes lever 38 to rotate counterclockwise and, through spring 41, to push down on lever 39. As a result, the contour plate 34 is pulled downwardly through a determined distance and the curved edge of the contour plate 34 displaces follower nose 29a, arm 29 and control rod 18 to the right. Thus, the additional fuel delivery required for starting is shutoff.

If the rpm of the engine continues to increase, then beyond a predetermined rpm the adaptor spring 7 is, due to the increasing forces of the centrifugal weights 3, continously and increasingly compressed until the adaptor sleeve 6 abuts against the regulator member 8. ln this rpm. range, in which only the adaptor sleeve 6 is displaced, the contour plate 34 is further pulled down until the upper terminal edge of guiding slot 340 eventually abuts against the cam 35. Thus, under full load conditions in which the finger 39a engages the upper curve-portion 34" which limits the full load fuel delivery, for each r.p.m. another maximal fuel delivery may be set. Since in full load condition the guide rod 21 is held immobile by the driver, the length of spring 31 of the accumulator 30 changes by virtue of the motion of arm 29 caused by the contour plate 34.

By suitably selecting the length ratio of

levers

38 and 39, a displacement of contour plate 34 may be obtained which is large with respect to the relatively short shift the adaptor sleeve 6 executes in relation to regulator member 8. Consequently, the extent of travel of finger 29a with respect to and on the curved edge portion of contour plate 34 will be relatively large.

If the rpm. increases further, the spring seat base 11 is displaced to the right by the adaptor sleeve 6 and by the regulator member 8, whereby the control spring 14 is compressed. During this last-named motion, the contour plate 34 is prevented by the cam 35 from executing a further downward displacement; as a result, the drag spring 41 is compressed. It is thus seen that by using drag spring 41, the travel of contour plate 34 may be limited without interfering with the motion of adaptor sleeve 6.

The r.p.m. control device described hereinabove not only ensures by simple means the required additional fuel delivery for good starting conditions, but also provides for a relatively easily adjustable adaptation of the fuel quantities to be injected in the full load range. By means of turning the shaft 37 the control path for full load conditions may be set, while by adjusting the nut 43 the shut-off point of the addtional fuel delivery for starting conditions and the beginning of the adaptation of the fuel quantities for full load conditions may be regulated.

The shaft 37 may be actuated by control mechanisms which are arranged externally of the centrifugal governor and may operate dependent upon atmospheric and temperature conditions.

We claim:

1. In a centrifugal governor for controlling the rpm. of diesel engines, said governor including weights displaced as a function of the rpm. and o eratively connected through a governor member to a contro rod ofa fuel in ection pump for regulating the delivery thereof by displacing said rod along a path, coupling means connecting said weights with an adjustable abutment determining the maximum fuel delivery of said injection pump by limiting said path, the improvement in said coupling means comprising:

A. a transfer element slidably disposed between said governor member and said weights and being displaceable by the latter; and

B. an adaptor spring connecting said transfer element with said governor member for transmitting the displacing forces of said weights from said transfer element to said governor member, said adjustable abutment being unaffected by the position of said governor member.

2. The improvement as defined in claim 1, wherein said transfer element is an adaptor sleeve slidably mounted on a drive shaft stub and displaceable thereon along a path coinciding with the path of displacement of said governor member.

3. The improvement as defined in claim 2, wherein said drive shaft stub has an axial bore, said governor member is provided with a pin rigidly secured thereto and axially extending therefrom, said pin is slidably disposed in said bore.

4. The improvement as defined in claim 1 including a first and a second lever both pivotable about a fixed common joint, said first lever is, at one end, pivotally secured to said transfer element and engages with its other, angularly bent end said second lever through a drag spring for transmitting the motion of said transfer element from said first lever to said second lever, said second lever is, at its end spaced from said common joint, coupled to said adjustable abutment.

5. The improvement as defined in claim 1, wherein said adjustable abutment is formed of a contour plate having a curved edge adapted to be engaged by a follower secured to said control rod, said contour plate is provided with a guide slot slidably engaged by a cam.

6. The improvement as defined in claim 5, wherein said cam is mounted on an eccentric affixed to the terminal face of an externally operable shaft.

7. The improvement as defined in claim 4, wherein said second lever is coupled to said abutment by means of a bolt slidably secured to said abutment, said bolt is adjustable with respect to said abutment by an adjusting nut threadedly engag ing said bolt.