JPH0849568A - Governor used for fuel injection pump of internal combustionengine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constantly generate uniform load to all buffer elements, and increase the service life of the buffer elements. SOLUTION: Lobes 53, 55 provided on a cam 37 and a carrier 31 are brought into contact with a stopper in both rotational directions of a drive shaft. Buffer elements are tightly fixed between the stoppers on the side opposite to the lobes 53, 55, a plurality of stoppers in contact with the lobes 53, 55 in the same rotational direction form stopper assemblies to be firmly coupled with each other, and the stopper assemblies are relatively rotatable to the stopper assembly in contact with the lobes 53, 55 in the respectively opposite rotational direction by a specified quantity of rotation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed governor used for a fuel injection pump of an internal combustion engine, which is provided with a centrifugal speed control mechanism, and the centrifugal speed control mechanism is supported by a support. A flyweight is provided, the flyweight can be moved and adjusted against a governor spring, and the adjustment movement of the flyweight is transmitted to a control rack that controls the pumping amount of the fuel injection pump. The centrifugal speed control mechanism is driven by a drive shaft of a fuel injection pump, the drive shaft is coupled to a driver provided in the centrifugal speed control mechanism, and the driver is On the end surface facing the support provided in the centrifugal speed control mechanism,
It has two pawls diametrically opposed to each other and projecting axially, said pawls being axial from the end face of the support body facing the drive body for the purpose of transmitting rotational movements. Cooperating with two pawls projecting in the direction which are arranged diametrically opposite one another on the support, a cushioning member is provided between the pawl provided on the support and the pawl provided on the drive body. Regarding the type of arrangement.

[0002]

A governor of this type is known from DE-A-4202732. In this known speed governor, a centrifugal speed control mechanism, which is coupled to a cam shaft of an injection pump and is rotationally driven by the cam shaft, uses an external movement of a flyweight via a lever mechanism to drive the fuel injection pump. A floating lever connected to the control rack is moved and adjusted, and thus the amount of fuel to be pumped is controlled in relation to the rotational speed. For this purpose, the camshaft of the fuel injection pump is connected to the support body of the centrifugal speed control mechanism that supports the flyweight. In order to prevent the camshaft vibration from propagating to the centrifugal governor and thus causing control inaccuracies, in known governors a vibration damping device is arranged at the connection between the support and the camshaft. Has been done. This vibration damping device has a pot-shaped capsule. Inside the capsule, two pawls are provided diametrically opposed to each other on a support and diametrically opposed to each other on a drive part rigidly connected to the camshaft of the fuel injection pump. The two located pawls are in each case. in this case,
Between the pawls, which are offset from each other by 90 °, there is arranged one damping member, preferably made of rubber, for damping purposes. In the known speed governor, the pawl provided on the entrainment part projects into the open part of the pot-shaped capsule, whereas the pawl provided on the support contacting the other side of the capsule. For this purpose, a notch in the shape of a pawl is machined into the bottom of the capsule. Transmission of the rotary movement of the camshaft of the fuel injection pump to the centrifugal governor is carried out in this case from a pawl provided on the entrainment part via a cushioning member to the pawl of the support body, in which case the pump camshaft Due to the vibration and rocking of the cushion and the pivoting of the pawls relative to each other, a compressive alternating load on the cushioning member is produced.

In this case, the known speed governor has the following drawbacks. That is, always 2 depending on the direction of force introduction.
Since only two cushions located opposite one another are involved in the damping, these two cushions have to carry the entire load. This significantly increases the mechanical wear of the shock absorber, especially in the case of highly loaded multi-cylinder injection pumps, and thus reduces the life of the shock absorber. This adversely affects the entire governor in terms of reliability.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to improve the speed governor of the type mentioned at the beginning so as to avoid the above-mentioned drawbacks and to always give a uniform load to all the cushioning members. Therefore, it is an object of the present invention to provide a speed governor in which the life of the cushioning member is extended.

[0005]

In order to solve this problem, in the structure of the present invention, the pawls contact the stoppers in both rotation directions of the drive shaft, and the pawls are provided between the stoppers. On the opposite side, a buffer member is tightened and fixed, and a plurality of stoppers that come into contact with the pawl in the same rotational direction form a stopper assembly that is rigidly coupled to each other. It is configured such that the stopper assembly that is in contact with the pawl in the opposite rotation direction can rotate relative to each other by a specified rotation amount.

[0006]

The speed governor according to the present invention has the following advantages over the conventional speed governor. That is, all of the four damping members are always involved in the damping, and the force applied to the vibration damping device is evenly distributed to all the four damping members. This reduces the maximum load on the individual dampers by about half, so that these dampers can be sized relatively small or they can absorb much higher loads during the constant work life of the vibration damper. Or the life can be significantly increased at the same load. This is achieved according to the invention by the arrangement of two stopper assemblies. Each of these stopper assemblies has a stopper that contacts each pawl in the same direction of rotation. In this case, the stoppers, which respectively come into contact with the pawls in one direction of rotation, are rigidly connected to one another to form one stopper assembly. The one stopper assembly is rotatable with respect to the other stopper assembly by a predetermined rotational distance, and the rotational movement is damped against the forces of the four damping members. In this case, it is also possible to provide more than two pawls each, as an alternative to the previous embodiment. In that case, these pawls are likewise brought into contact with each one stop of the stopper assembly in both directions of rotation. The number of cushioning members clamped between the stoppers on the side opposite the pawls is correspondingly increased.

According to the invention, the first stopper assembly is structurally simpler by virtue of the provision of four stoppers projecting axially from the bottom of the capsule, due to the capsule already present in the vibration damping device. Can be formed. In this case, this capsule is
It cooperates with an intermediate plate arranged between the flyweight support of the centrifugal speed control mechanism and the support. This intermediate plate also has four axially protruding stoppers to form a second stopper assembly. The required relative rotational movement between the capsule and the intermediate plate is obtained based on the setting of the notches accommodating the pawls. In this case, the two cutouts, which are arranged one above the other, are formed in the opposite direction of rotation in a direction which is larger than the construction space required by the pawls by a defined dimension. in this case,
The size of the stopper provided on the intermediate plate and protruding into the notch of the capsule is taken into consideration. Alternatively, it is also possible to form the two stopper assemblies with two intermediate plates. In that case, the axially projecting stoppers of the two intermediate plates project into the capsule of the vibration damping device.

In order to prevent the shock-absorbing member from being mechanically damaged due to the friction at the sharp transition portion of the notch provided on the bottom of the capsule, the edge is chamfered obliquely. It is advantageous. Another means for avoiding such damage of the cushioning member is obtained by placing the cushioning member directly in a notch provided in the bottom of the capsule and extending between the stoppers. In this case, the buffer member is guided in the axial direction based on the contact of the buffer member with the intermediate plate. Such an arrangement form further has the following advantages. That is, since the cushioning member does not project beyond the capsule wall and thus does not increase the space for forming the capsule, the size of the speed governor according to the present invention is increased by the size of the intermediate plate. This allows retrofitting to known speed governors. Moreover, in this case, very little manufacturing and assembly work is required due to the retrofitting of only one additional component.

The capsule of the vibration damping device can easily be manufactured by preforming, for example sintering. This also means that little manufacturing effort is required.

Yet another advantage is obtained by using the cushioning member preloaded. As a result, it is possible to reduce the strain tension of the cushioning member during operation. This is because the operation of the known speed governor does not require the preload stroke (which is followed by the damping stroke) that occurs in the two completely relaxed cushioning members.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

In the speed governor shown in FIG. 1 and corresponding to the structure of a known speed governor (limited to the description of the components important to the present invention), the drive shaft 3 protruding into the casing 1 of the speed governor. A cam shaft of a fuel injection pump (not shown), which is preferably adjacent to the speed governor, drives a centrifugal speed control mechanism 5 fixed to the drive shaft 3. The governor sleeve 7 that acts as an adjusting member of the centrifugal speed control mechanism 5 is connected to two flyweights 29 of the centrifugal speed control mechanism 5 via a bell crank 8. The governor sleeve 7 acts via a pin 9 on one end of a pivotable floating lever 11. The other end of the floating lever 11 is rotatably connected to a control rack 13 of a fuel injection pump (not shown). A pin 9 for connecting the floating lever 11 and the governor sleeve 7 to each other is supported by a slider 17 slidably arranged along a guide pin 15. The floating lever 11 has a slider guide 19
A slide 21 is arranged in the slide guide 19. A link lever 23 acts on the slider 21, and the link lever 23 is connected to a control lever 25 for transmitting a change in the control rack position desired by the driver via a bearing fixed to the casing.

In order to transmit the rotational movement of the drive shaft 3 to the centrifugal speed control mechanism 5 and at the same time to prevent the vibration from propagating to the centrifugal speed control mechanism 5, the drive shaft 3 is subjected to a centrifugal control via a vibration damping device 27. Support for accommodating two threaded pins 32 for accommodating the two flyweights 29 of the speed mechanism 5 and one governor spring 30 acting against the outward movement of these flyweights 29. It is connected to 31.

For this purpose, the end of the drive shaft 3 which projects into the casing 1 of the governor has a conical diameter reduced diameter portion 33. The diameter reduced portion 33 transitions to an end portion having a constant diameter. Threads 35 are arranged at this end. The end of the drive shaft 3 which projects into the casing 1 is inserted into a driver 37 in the form of a sleeve.
The entrainment 37 has a diameter reduced portion 39 inside which also corresponds to the conical diameter reduced portion 33 of the drive shaft 3.
The conical diameter-reduced portion 39 again rapidly transitions to a larger diameter at its smallest diameter, thereby forming a shoulder 41 inside the driver 37. An intermediate sleeve 45 is provided in a region of the inner wall of the entrainment body 37 continuing from the shoulder portion 41. The intermediate sleeve 45 is in contact with the shoulder portion 41. The inner wall surface of the intermediate sleeve 45 has threads 49. Since the screw thread 35 of the drive shaft 3 is screwed into the screw thread 49, the drive shaft 3 is axially tightened to the conical diameter reducing portion 39 provided in the driving body 37. Therefore, a frictional connection is formed between the drive shaft 3 and the driver 37. An end portion of the driving body 37 on the side opposite to the end portion of the drive shaft 3 has a diameter enlarged portion on the outer peripheral surface. The enlarged diameter portion is transferred to the plate 51 that limits the entrainment body 37 via the step portion. Two pawls 53 located diametrically opposite each other are arranged on the side of the plate 51 facing the end of the drive shaft 3. This pawl 53 is the vibration damping device 2
7 through the support 31 as shown in FIGS.
Cooperates with two pawls 55 provided on the. The pawls 55 provided on the support body 31 are arranged on the cylindrical outer peripheral surface of the support body 31 so as to be positioned diametrically opposite each other. In this case, the pawls 55 are arranged so as to be displaced from each other by 90 ° with respect to the threaded pins 32 that house the flyweights 29 of the centrifugal speed control mechanism 5.
The support 31 has a concentric hole 59 inside. The driver 37 is guided to the hole 59 via the outer peripheral surface thereof. In this case, the shoulder 61, which limits the hole 59 on the side opposite the driver 37, forms a stopper. The end face 63 of the driving body 37 on the side opposite to the plate 51 is in contact with this stopper. Support 31 and this support 31
Between the driving body 37 guided inside, the vibration damping device 2
A pot-shaped capsule 65 forming a part of 7 is arranged. The capsule 65 has a cylindrical capsule wall 66.
And an annular capsule bottom 67 integrally connected to the capsule wall 66. In this case, the capsule 65
Are guided to the outer peripheral surface of the driver 37 via concentric holes 68 provided in the capsule bottom 67.

The structure of the capsule 65 improved in comparison with the known speed governor, and further the capsule 65 and the support 31.
An intermediate plate 81 (not shown in FIG. 1) disposed between
The structure of is found in the enlarged exploded view shown in FIG.

The capsule 65 has four notches 69 evenly distributed around the entire circumference of the capsule bottom 67 for the purpose of accommodating the pawls 53 and 55. These notches 69 are one end portions on the peripheral surface side located in the same rotation direction of the drive shaft 3, respectively, and the capsule bottom portion 67 in the axial direction.
It is limited by a stopper 71 protruding from the inside of the capsule 65. The intermediate plate 81 has four notches 83 equally distributed for the purpose of accommodating the pawls 53 and 55.
have. One end of each of these notches 83 on the peripheral surface side has stoppers 85 that project in the direction of the capsule 65 in the axial direction. In this case, these stoppers 85 are provided on the capsule 65. The notch 83 is restricted with respect to the stopper 71 in the opposite rotation direction of the drive shaft 3.

Both notches 69 and 83 are formed by these notches 6.
The radial widths of 9,83 are designed to correspond to the widths of the pawls 53,55. In this case, the intermediate plate 81 that protrudes into the notch 69 of the capsule 65 in the assembled state.
The stopper 85 corresponds to the width of the pawls 53 and 55.
The arc lengths of the notches 69 and 83 in the rotation direction are 1 each.
Capsule 65 that forms one solid stopper assembly
The intermediate plate 81 and the intermediate plate 81 are designed to be rotatable relative to each other by a specified amount in the assembled state.

FIG. 3 shows the assembled vibration damping device 2.
A first embodiment of No. 7 is shown in a view from the inside of the capsule 65. The components shown in FIG. 2 and the entrainment body 37 are assembled to each other via a pawl 53 provided on the entrainment body 37. In this case, the pawls 53 and 55 include a capsule bottom 67 and an intermediate plate 81. Into the partially overlapped notches 69, 83 provided in the. Claw 5
In this case, 3, 55 respectively contact the stopper 71 of the capsule 65 in one rotation direction and the stopper 85 of the intermediate plate 81 in the opposite rotation direction. Each stopper 71;
85 are firmly coupled to each other via the capsule 65 or the intermediate plate 81. The stoppers 71, 85 may be formed as protrusions bent up at a right angle. Stopper 7
1, 85 are loaded by the cushioning member 91 on the side opposite to the pawls 53, 55, respectively. In this case, four buffer members 91 are provided. These cushioning members 91 are preloaded so that each two adjacent stoppers 71,
These cushioning members 9 are clamped between 85 and
1 provides damping.

FIG. 3 further shows in dashed lines the contours of the cutouts 69, 83, which are in contrast to one another. This notch 6
On the basis of the remaining free surfaces of 9, 83, the capsule 65 relative to the intermediate plate 81 in both directions of rotation of the drive shaft 3.
, Each rotational movement for damping vibration is defined. In this case, in order to avoid a frictional connection in the buffer member 91, the free edge of the notch 69 is chamfered obliquely in the direction of rotation.

The second embodiment shown in FIG. 4 has a cutout 69.
And only regarding the configuration of the stopper 71 of the capsule 65,
This is different from the first embodiment shown in FIG. Therefore, only the differences will be described in detail.

In the second embodiment, instead of the notch 69, a partially annular through hole is provided in the capsule bottom 67.
This through hole corresponds to the width of the pawls 55, 53 and the cushioning member 91, and extends completely between the stoppers 71, so that the cushioning member 91 makes complete contact with the intermediate plate 81 in the axial direction, and There is no risk of frictional connection. In this case, the stopper 71 of the capsule 65 is designed so that the stopper 71 surely covers the free end of the notch 83, in which case the capsule 71 is similar to the first embodiment shown in FIG. A specified rotational distance D of relative movement between 65 and the intermediate plate 81 is maintained.

FIG. 5 shows possible means for increasing the rigidity of the capsule 65 shown in FIG. In this case, an additional reinforcing ring 93 is added to the cylindrical capsule wall 66.
Is arranged.

The governor used in the fuel injection pump of the internal combustion engine according to the present invention operates as follows. During operation of the fuel injection pump driven by the internal combustion engine to be supplied with fuel, the drive shaft 3 is brought into a rotational movement proportional to the engine speed by the fuel injection pump 3. This rotational movement is caused by the entrainment body 37 and the pawl 53 provided on the entrainment body 37, and the cushioning member 9 inside the capsule 65.
1 is transmitted to the pawl 55 provided on the support 31. Based on the rotational movement of the support body 31 accommodating the flyweight 29, the flyweight 29 moves to the governor spring 3
It is pushed outward against the spring force of 0 and moves the governor sleeve 7 in the direction of the drive shaft 3 via the bell crank 8. When the control lever 25 and the link lever 23 are in the stationary state, the floating lever 11 moves the slider 2
1, the control rack 13 is moved in the direction of reducing the fuel pumping amount, that is, in the direction opposite to the drive shaft 3, and thereafter, the rotational speed of the internal combustion engine, that is, the centrifugal speed control mechanism. An equilibrium occurs between the number of revolutions of 5 and the position of the control rack 13 which defines the amount of fuel to be pumped. In this case, the fuel pressure feed amount can be changed in a known manner via the control lever 25 when the desired rotation speed is changed.

In this case, in order to prevent the vibration generated in the drive shaft 3 from propagating to the centrifugal speed control mechanism 5, the buffer member 91 arranged between the pawls 53 and 55 in the capsule 65 is used as a force. During transmission, this vibration is damped.

At this time, a relative rotational movement occurs between the capsule 65 and the intermediate plate 81 within the rotational distance D defined by the dimensions of the notches 69 and 83. When this relative rotational movement is performed, the cushioning member 91 is contracted. Based on the arrangement of the two stopper assemblies, not only the cushioning member 91 that directly contacts the pawls 53; 55 for introducing the force in each force introduction direction is involved in the vibration damping, but also each pawl 5
3; the force introduction direction (relative rotation direction between the capsule and the intermediate plate), which does not contact the force introduction side of 55; Advantageously, the damping member 91, which contacts each pawl in the opposite direction, is also realized to participate in the vibration damping. Therefore, only one-fourth of the force transmitted to the vibration damping device 27 is always absorbed by each individual damping member 91. This results in a significant increase in the service life and service life of the entire vibration damping device, while maintaining the structural dimensions of the damping element.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a known speed governor.

FIG. 2 is an exploded perspective view of a vibration damping device used in the speed governor according to the present invention.

FIG. 3 is a cross-sectional view of a capsule used in the vibration damping device according to the first embodiment of the present invention.

FIG. 4 is a sectional view of a capsule used in a vibration damping device according to a second embodiment of the present invention.

5 is a cross-sectional view showing a reinforcing ring of a capsule wall of the vibration damping device shown in FIG.

[Explanation of symbols]

1 casing, 3 drive shaft, 5 centrifugal speed control mechanism,
7 Governor sleeve, 8 Bell crank, 9 pin, 11 Floating lever, 13 Control rack, 15 Guide pin, 17 Slider, 19
Slide guide, 21 slide, 23 link lever,
25 control lever, 27 vibration damping device, 2
9 Fly weight, 30 Governor spring, 3
1 Support, 32 Threaded Pin, 33 Diameter Reduced Part, 35 Threaded, 37 Carrying Body, 39 Diameter Reduced Part, 41 Shoulder, 45 Intermediate Sleeve, 51
Plate, 53, 55 claw, 59 hole, 61 shoulder,
63 end face, 65 capsule, 66 capsule wall, 67 capsule bottom, 68 hole, 69 notch, 71 stopper, 81 intermediate plate, 83 notch, 85 stopper, 91 cushioning member, 93 reinforcing ring, D rotation distance

Claims (10)

[Claims] 1. A speed governor used in a fuel injection pump of an internal combustion engine, comprising a centrifugal speed control mechanism (5), the centrifugal speed control mechanism (5) being provided on a support (31). The flyweight (29) is supported, the flyweight (29) is movable and adjustable against the governor spring (30), and the adjusting movement of the flyweight (29) is performed by the fuel injection pump. The centrifugal speed control mechanism (5) is driven by a drive shaft (3) of a fuel injection pump, and the drive shaft ( 3) is coupled to an entrainment body (37) provided in the centrifugal speed control mechanism (5), and the entrainment body (37) is the support body provided in the centrifugal speed control mechanism (5). Diametrically facing each other on the end faces facing (31) It has two pawls (53) that are located in line and project in the axial direction.
3) said support (3) for the purpose of transmitting rotational movement.
1) cooperating with two pawls (55) axially projecting from the end face facing the entrainment body (37), which are arranged diametrically opposite one another on the support body (31), In the type in which the cushioning member (91) is arranged between the pawl (55) provided on the body (31) and the pawl (53) provided on the entrainment body (37), the pawl (91) 53, 55) are in contact with the stoppers in both directions of rotation of the drive shaft (3), respectively, and between the stoppers, the cushioning member (91) is provided on the side opposite to the pawls (53, 55). A plurality of stoppers, which are fixed by tightening and contact the pawls (53, 55) in the same rotational direction, respectively, form stopper assemblies that are firmly coupled to each other, and the stopper assemblies are
An adjusting mechanism used in a fuel injection pump for an internal combustion engine, characterized in that the adjusting mechanism is rotatable relative to a stopper assembly that comes into contact with the pawls (53, 55) in opposite rotation directions by a specified rotation amount. Speed machine. 2. A cushioning member (91) is provided on the support (3).
1) and the entrainment body (37) are arranged in a pot-shaped capsule (65), which comprises a cylindrical capsule wall (66) and an annular capsule bottom (6).
7) and the capsule bottom (67) is provided with a notch (69) for accommodating the pawl (53, 55). 3. A notch (69) in the bottom of the capsule (67) for accommodating the pawl (53, 55) provides a defined pivoting movement of the pawl (53, 55) with respect to the capsule (65). One end of the notch (69), which is designed to allow it, and which is respectively located in the same direction as the direction of rotation of the drive shaft (3), has a capsule bottom ( 67) having a stopper (71) projecting from it, said stoppers (71) being rigidly connected to one another via a capsule bottom (67) to form a first stopper assembly. The speed governor described in 2. 4. The support (31) and the capsule (6)
5), an intermediate plate (81) is arranged between the intermediate plate (81) and the intermediate plate (81), and the intermediate plate (81) is provided with four notches (83) for accommodating the pawls (53, 55). Of (83),
The extension of the drive shaft (3) in the direction of rotation enables a defined swiveling movement of the pawls (53, 55) with respect to the intermediate plate (81), the notches (83) respectively being capsules. At one end on the side opposite to the stopper (71) provided in the notch (69) provided in (65),
Each notch (6) protruding axially and of the capsule (65)
9) limited by a stopper (85) projecting into it, said stoppers (85) being rigidly connected to one another via said intermediate plate (81) to form a second stopper assembly. Any one of items 1 to 3
The speed governor described in the item. 5. The entrainment body (3), wherein a capsule (65) and an intermediate plate (81) are arranged in contact with each other and penetrate through the partially overlapping notches (69, 83).
7) and the support (31) with pawls (53,
55) contact the stopper (85) of the intermediate plate (81) in one rotation direction of the drive shaft (3) and the stopper (7) of the capsule (65) in the opposite rotation direction.
The buffer member (91) which is in contact with 1) and is pre-loaded between the stoppers (71, 85) and fixed by tightening the stopper members (71, 85) to the pawls (53, 55). The speed governor according to claim 4, which is held in contact with the speed governor. 6. The cushioning member (91) is a capsule (6).
5), the ends of the cutouts (69) of the capsule (65) opposite the associated stopper (71) are beveled towards the capsule bottom (67) respectively. The speed governor according to claim 5, which is formed as a part. 7. The stopper (7) of the capsule (65) in the free range adjacent to each pawl (53, 55) of the notch (83) provided in the intermediate plate (81) is the entire swivel range.
The stopper (71) provided on the capsule bottom (67) is designed so as to be surely covered by 1), and the capsule bottom (67) belongs to the range where the cushioning member (91) is located. The speed governor according to claim 5, wherein the cushioning member (91) is completely penetrated between the stoppers (71) and is in direct contact with the intermediate plate (81). 8. The speed governor according to claim 7, wherein the cylindrical capsule wall (66) is surrounded by a reinforcing ring (93). 9. The stoppers (71; 85) are formed integrally with the capsule (65) or the intermediate plate (81), and the stoppers (71, 85) are machined and the capsule bottom portion (71) is formed. 67) or the intermediate plate (8)
5. Governor according to any one of claims 1 to 4, which is formed from a part of the material of the cutout (69; 83), which is bent 90 ° from the plane of 1). 10. The dimension of the width of the pawls (53, 55) and the width of the stopper (85) arranged on the intermediate plate (81) are the same in the radial direction with respect to the axis of the drive shaft (3). The speed governor according to any one of claims 1 to 4, which is formed on the.