JP3184006B2 - Liquid metering pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a liquid metering pump used for supplying various amounts of lubricating oil in accordance with the operating condition to an engine of a motorcycle.

[0002]

2. Description of the Related Art Among the above-mentioned pumps, there are pumps conventionally constructed as follows.

That is, a cylinder hole is formed in a pump case, and a plunger is fitted into the cylinder hole so as to be slidable in the axial direction, and a space closed by an axial end of the plunger in the cylinder hole is a pump chamber. It has been.
An electric motor is attached to the pump case,
The plunger is connected to the motor by interlocking means such as a cam mechanism.
Ri is interlocked, the plunger with the driving of the motor is caused to reciprocate at a constant stroke in the axial direction
It has become.

[0004] Then, with respect to the pump chamber to expand in forward movement of the plunger, while the liquid is sucked from the liquid tank, ibid liquid from ibid pump chamber to reduce at backward of the same plunger toward the inlet side It is designed to be ejected.

[0005]

By the way, the above pump
In the interlocking means in
The joints of the two members to be joined
Load on each other, this load
The joint portion is worn, and an error occurs in the discharge amount of the liquid by the pump , resulting in a problem that accuracy of the supply amount is reduced.

[0006]

SUMMARY OF THE INVENTION The present invention has been made focusing on the above circumstances, supply amount of accuracy and an object thereof is to provide a liquid metering pump satisfactorily maintained for a long time.

[0007]

The feature of the present invention for achieving the above object is that a cylinder hole 5 is provided inside.
2 and the cylinder hole 52
A plunger 53 fitted slidably in the axial direction;
The pump case 39 is supported on the axis 40 of the
Stepping mode that is alternately driven and stopped
Motor 69 and an output shaft 70 of the stepping motor 69.
Attached to the end of the base that protrudes beyond the radial dimension
And the axis of the plunger 53
Through one end in the radial direction, and each end
To engage with the radial direction toward the outer end of the projecting end of the rotor 71
And at the center of the penetration to the plunger 53
Camshaft 74 which can be swiveled by the pump case
39 fixed radially outward of the plunger 53
The plunger 53 is arranged at a radially symmetric position
A pair of cam projections 73, 73 which engage with the cam shaft 74.
The plunger 5 in the cylinder hole 52.
The space closed by the other axial end of the pump chamber is
54, and by driving the stepping motor 69,
The output shaft 70, the rotating body 71, the cam shaft 74, and the
The jaws 53 rotate sequentially around the axis 40 in conjunction with each other
So that the camshaft 74 and the one
The cam shaft 74 is engaged with the pair of cam projections 73 by the cam engagement.
Moves the plunger 53 at a constant stroke in its axial direction.
To reciprocate and expand by the forward movement of the plunger 53.
The lubricating oil (liquid) 25 is sucked into the pump chamber 54.
On the other hand, the same pump as above
Lubricating oil (liquid) 25 from chamber 54 to the supply side
The point is that the ink is ejected .

[0008]

[Operation] The operation of the above configuration is as follows.

The terms in parentheses described below correspond to the terms in the claims.

First, as described above, the stepping mode
The output shaft 70, the rotating body 71,
The cam shaft 74 and the plunger 53 are sequentially
When rotating together around the axis 40, the rotating body 71
At the radially outer end of the protruding end with the larger radial dimension.
Each end of the cam shaft 74 is locked.
Therefore, the camshaft 74 with respect to the rotating body 71
Is locked at the axis 4 which is the center of rotation of the rotating body 71.
Both are greatly separated from 0, and both of these 71, 7
The load given to each other at the joints of 4 is small
Is done.

Therefore, the stepping motor 69 is driven
The rotation and stop are repeated.
The joints of the shafts 74 are subjected to repeated loads.
However, as described above, since this load is suppressed to a small value,
Wear of the joint between the two 71 and 74 is suppressed.

Second, as described above, camshaft 74 and camshaft
The pair of cam projections 73, 73 engaged with the
Are arranged at symmetrical positions in the radial direction of the
The cam shaft 74 is connected to each of the cam projections 73 at both ends.
Reciprocating in the axial direction of the shaft center 40 by engaging the cam with good balance
Be moved.

[0013] Therefore, the above-mentioned
When the lancer 53 is reciprocated in its axial direction,
The cam shaft 74 is prevented from prying the plunger 53.
In response, the plunger 53 is
Squeezing the inner peripheral surface of the dowel hole 52 is suppressed.
Wear of the inner peripheral surface of the cylinder hole 52 is suppressed.

Third, as described above, the cam shaft 74 is
Swingable around the penetrating part to the plunger 53
Therefore, if the pair of cam projections
73, there is a slight dimensional error between the camshafts 7
4 for cam engagement with each cam projection 73 at each end side.
Even if the lance is slightly displaced,
By swinging with respect to the plunger 53, the cam shaft
74 is prevented from prying the plunger 53.
You.

Therefore, also in this respect, the plunger 53
Is prevented from prying the inner peripheral surface of the cylinder hole 52.
And the inner peripheral surface of the cylinder hole 52 is more reliably worn.
Is suppressed.

Fourth, as described above, the plunger 5
3, by the stepping motor 69 and the rotating body 71
Since the combined bodies are juxtaposed on one axis 40,
The hydraulic pump (pump) 27 extends along the axis 40.
It tends to be large in the direction.

Therefore, the plunger 53 is disposed radially outward.
A pair of cam projections 73 cam-engaged with the cam shaft 74,
73, so that these cam projections 7
3, 73 in the direction along the axis 40,
It can be prevented that they are juxtaposed with the body.

Therefore, the hydraulic pump (pump) 27 is
It does not become large in the direction along the axis 40.
Is stopped.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)

FIGS. 1 to 9 show the first embodiment.

In FIG. 2, reference numeral 1 denotes a two-cylinder two-cycle engine mounted on a motorcycle.
Has a cylinder 2, a piston 3, a crankcase 4, and a crankshaft 5. Each cylinder 2 has an intake port 6 and an exhaust port 7, respectively. Reference numeral 8 denotes a spark plug.

A carburetor 10 is connected to the intake port 6. The carburetor 10 has a piston valve 11, which is urged by a spring 13 in a direction to close an intake passage 12 of the carburetor 10.

The piston valve 11 is connected to a throttle grip 17 via a wire 16. The intake passage 12 is opened / closed by the operation of the piston valve 11 accompanying the turning operation of the throttle grip 17, that is, the throttle opening is adjusted. And
As the throttle opening increases, a large amount of air-fuel mixture is drawn into the cylinder 2 accordingly.

On the other hand, the exhaust port 7 is provided with an exhaust regulating valve 19 for opening and closing the upper edge side of the exhaust port 7 in accordance with the rotation speed of the engine 1 and adjusting the exhaust timing to improve the combustion efficiency. I have. This exhaust control valve 1
9 is driven by a servomotor 21.

Reference numeral 24 denotes a lubricating oil tank, which supplies a lubricating oil 25 as a liquid in the lubricating oil tank 24 to a one-way valve 26,
A plunger type hydraulic pump 27 that supplies the cylinder 2 through the intake port 6 is provided. 28 is an oil filter.

In addition, 30 is an engine speed sensor, 3
1 is a throttle opening sensor, 32 is a crankcase pressure sensor, 33 is an exhaust pressure sensor, 34 is an engine temperature sensor,
35 is an oil pump rotation sensor. A control unit 36 that electrically and electronically controls the ignition plug 8, the exhaust adjustment valve 19, and the hydraulic pump 27 based on the detection signals of these sensors 30 to 35 is provided. The symbol A in FIG. 2 means that the devices with this symbol are electrically connected to the control unit 36, respectively. Reference numeral 37 denotes an alarm device.

The hydraulic pump 27 will be described with reference to FIG. 1 and FIGS.

The hydraulic pump 27 has a pump case 39 made of resin. The pump case 39 has a bowl-shaped case body 41 having a shaft center 40 oriented vertically, and the upper end opening of the case body 41 can be freely opened and closed. Close and screw with bolt 42
And a lid 43 to be fixed .

The inside of the pump case 39 is a case chamber 45. A cylindrical metal block 46 is fitted into the bottom of the case chamber 45, and the block 46 is attached to the case body 41 by a pair of bolts 47. , 47 for fixing . 48 is a ground terminal.

A fitting hole 49 is formed in the block 46 on the shaft center 40, and a cylindrical metal distributor 50 is rotatably fitted around the shaft center 40 in the fitting hole 49. . A resin stopper 51 is fitted to the lower end of the distributor 50.

The inside of the distributor 50 is a cylinder hole 52, into which a metal plunger 53 is slidably fitted in the axial direction, that is, in the vertical direction. In the cylinder hole 52, a space closed by a stopper 51 and a lower end, which is an axial end of the plunger 53, is a pump chamber 54.

A first notch 56 and a second notch 57 are formed on each side of the block 46 on the left and right sides (referred to as the direction toward FIG. 1 and the same hereinafter). A suction port 58 for communicating the outside of the pump case 39 with the first notch 56 is formed in the case body 41, and the suction port 58 is connected to the lubricating oil tank 24.

The block 46 has a first suction hole 60 extending from the first notch 56 to the fitting hole 49, and a second suction hole 61 communicating from the second notch 57 to the fitting hole 49. I have. Further, a first discharge hole 62 and a second discharge hole 63 are formed in the front and rear portions of the same block 46, and a first discharge port 64 that connects the first discharge hole 62 to the outside of the pump case 39, A second discharge port 65 for connecting the second discharge hole 63 to the outside of the pump case 39 is formed in the case main body 41.

The distributor 50 is provided with a communication hole 66 at a part in the circumferential direction.

A drive mechanism 68 for driving the distributor 50 and the plunger 53 to expand and contract the pump chamber 54 is provided.

The drive mechanism 68 is connected to the pump case 39.
Has a stepping motor 69 which is detachably attached to the upper surface by the bolt 42. This step
An output shaft 70 of the ping motor 69 is located on the shaft center 40 and protrudes into the case chamber 45.
Is attached. This rotating body 71 is
The projecting end is larger than the radial dimension of the base on the ping motor 69 side.
Department of it has been bigger.

On the other hand,As described above, the pump case 39
Fixed toOn the upper end surface of the block 46The above
Of the plunger 53 radially outward of the plunger 53
Radially symmetrical positionPlacedA pair of cam projections 73, 73
Are formed. In addition, the plunger 53Axial direction
Is the end ofUpendThe part has a metal cam shaft 7 in the radial direction.
4 are penetrated. In this case, the above distribution
A pair of left and right long holes 75, 75 long vertically
Are formed, and these long holes 75, 75 are connected to the cam shaft 74.
Each end ofPart sidePenetrates and the camshaft 74Each end
The rotating body 71 is rotated so as to rotate with the rotating body 71.
Of the protruding end ofAt each radial endLocked
You.

When the plunger 53 is moved up and down with respect to the distributor 50, the cam shaft 74 is moved.
Move up and down in each of the long holes 75, and
Also moves up and down relatively.

When the rotating body 71 is rotated via the output shaft 70 by the driving of the stepping motor 69, the distributor 50 and the plunger 53 are rotated together with the plunger 53 via the cam shaft 74. .

A spring 76 is provided between the distributor 50 and the plunger 53 and the rotating body 71. The spring 76 resiliently pushes the distributor 50 into the fitting hole 49, and the plunger 5.
3 is elastically pushed into the cylinder hole 52. In addition, the cam shaft 74 is pushed down accordingly, and each end of the cam shaft 74 is elastically engaged with each of the cam projections 73, 73.

Each end of the cam shaft 74 can swing up and down slightly about the penetrating portion to the plunger 53, so that each end of the cam shaft 74 is 73 is prevented from hitting one side.

The oil pump rotation sensor 35 is formed of a coil, is provided so as to surround the rotating body 71 and the cam shaft 74, and is supported by the lid 43. The oil pump rotation sensor 35 is slightly eccentric with respect to the shaft center 40. Then, when the cam shaft 74 rotates together with the rotating body 71 with the operation of the stepping motor 69,
The cam shaft 74 comes into contact with a part of the eccentric coil only once during one rotation. Then, the plunger 53, the distributor 50, the block 4
6, a current flows through the bolt 47 and the ground terminal 48, and by detecting this, the rotation speed of the distributor 50 and the plunger 53 (the rotation speed of the stepping motor 69) is detected.

In addition, reference numeral 78 denotes an air vent hole, and 79 denotes a stopper screw.

The case chamber 45 is filled with the lubricating oil 25 supplied from the lubricating oil tank 24 through the suction port 58.

By the driving of the stepping motor 69, the output shaft 70, the rotating body 71, the cam shaft 74,
And the plunger 53 are sequentially interlocked around the axis 40.
And the camshaft associated with this rotation.
74 and the pair of cam projections 73, 73.
The cam shaft 74 causes the plunger 53 to move
Reciprocating with a constant stroke in the direction
You.

This will be described more specifically.
When the rotator 71 is rotated by the driving of the ping motor 69 (arrow B in the figure), and the cam shaft 74 that rotates with the rotator 71 rides on the left and right cam projections 73, 73 as shown, the plunger 53 rises (outbound)
Then, the pump chamber 54 expands to a negative pressure. At this time, as shown in the drawing, the communication hole 66 matches the first suction hole 60, and the lubricating oil 25 in the case chamber 45 passes through the first suction hole 60 and the communication hole 66 to the pump chamber 54. It is inhaled (arrow C in the figure).

When the rotating body 71 further rotates by about 90 ° from the above state, the cam shaft 74 is disengaged from the cam projections 73, 73 and is pushed down by the spring 76, whereby the plunger 53 descends (returns). The pump chamber 54 is reduced, and the lubricating oil 25 in the pump chamber 54 is pressurized. At this time, the communication hole 66 matches the first discharge hole 62, and the lubricating oil 25 in the pump chamber 54 passes through the communication hole 66, the first discharge hole 62, and the first discharge port 64. And is discharged out of the pump case 39 (arrow D in the figure).

Further, when the rotating body 71 rotates by about 90 °, the cam shaft 74 rides on the cam projections 73 again, the plunger 53 rises (forward movement), and the pump chamber 54 expands to a negative pressure. . At this time, the communication hole 66 matches the second suction hole 61, and the lubricating oil 25 in the case chamber 45 is sucked into the pump chamber 54 through the second suction hole 61 and the communication hole 66 ( Arrow E in the figure).

Further, when the rotating body 71 rotates about 90 °, the cam shaft 74 is again disengaged from the cam projections 73, 73, is pushed down by the spring 76, and the plunger 53 is lowered (returned), and the pump chamber 54 is reduced. Then, the lubricating oil 25 in the pump chamber 54 is pressurized. At this time, the communication hole 66 matches the second discharge hole 63, and the lubricating oil 25 in the pump chamber 54 passes through the communication hole 66, the second discharge hole 63, and the second discharge port 65. And is discharged out of the pump case 39 (arrow F in the figure).

As described above, the reciprocating motion of the plunger 53 is repeated at a constant stroke corresponding to the height of the cam projection 73, and the reciprocating motion is repeated twice per rotation.

The lubricating oil 25 discharged from the hydraulic pump 27 is supplied into the cylinder 2 through the intake port 6.

In the above case, when bubbles are sucked into the pump chamber 54 together with the lubricating oil (liquid) 25 along with the expansion of the pump chamber 54 due to the rise (forward movement) of the plunger 53, the pump chamber 54 rises (forward movement). The compression ratio R of the pump chamber 54 is set such that when the pump chamber 54 is reduced due to the subsequent lowering (return) of the plunger 53, substantially all of the bubbles are discharged from the pump chamber 54.

The above-described compression ratio R is defined as V ₀ when the maximum volume when the pump chamber 54 is expanded and V ₁ when the minimum volume when the pump chamber 54 is reduced.

R = V ₀ / V ₁

Is shown.

When the pump chamber 54 is expanded by driving the plunger 53 during the operation of the hydraulic pump 27 as described above, even if air bubbles are sucked into the pump chamber 54 together with the lubricating oil 25, the next plunger When the pump chamber 54 is reduced by the driving of the pump 53, the air bubbles are immediately discharged from the pump chamber 54.
The stagnation of the bubbles in the pump chamber 54 is very short, and thus the accuracy of the supply amount is kept good.

In FIG. 2 and FIGS. 7 to 9, the supply amount Q of the lubricating oil 25 to the engine 1 by the hydraulic pump 27 is determined to be an appropriate amount according to the operating condition of the engine 1.

In FIG. 7, the engine speed sensor 30
An engine rotational speed detected by, the two-dimensional map for the throttle opening detected by the throttle opening sensor 31, the reference supply amount Q ₀ is determined by the control unit 36.

In FIG. 8, the crank chamber pressure sensor 32
According to the map related to the crank chamber pressure detected by the exhaust pressure or the exhaust pressure detected by the exhaust pressure sensor 33,
Regulated supply amount control unit 36 △ Q _p is determined.

In FIG. 9, a map relating to the engine temperature detected by the engine temperature sensor 34 is used.
Regulated supply amount control unit 36 △ Q _t is defined.

Then, the above Q = Q ₀ + △ Q _p + △ Q _t is set, and the control unit 36 performs step
The number of revolutions of the ping motor 69 is determined, and an appropriate amount of the lubricating oil 25 is supplied according to the operating condition of the engine 1.

[0063] The stepping motor 69 is driving the dynamic and stop so as to alternately repeated, at the time of driving, because the distributor 50 and the plunger 53 is caused to instantaneously rotate the fitting hole 49, each of these components This has the effect of preventing leaks between them.

The stepping motor 69 and the rotating body 7
When the rotation speed of the camshaft 74 or the rotation speed of the camshaft 74 becomes inconsistent, it is considered that the supply of the lubricating oil 25 to the engine 1 by the hydraulic pump 27 tends to be insufficient. Therefore, when the inconsistency is detected, the control unit 36 The ignition timing is retarded (or the ignition is thinned out), and / or the exhaust control valve 19 is closed to lower the engine output. Then, in this case, an alarm such as lighting of a warning lamp of the alarm device 37 is issued.

Although the above description is based on the illustrated example, the liquid may be a drug solution, blood, or the like.

(Embodiment 2)

FIGS. 10 and 11 show the second embodiment.

According to this, the distributor 50 in the first embodiment is omitted, and the cylinder hole 52 is formed directly in the block 46. In addition, the plug 51 is also removed, and a space closed by the lower part of the plunger 53 and the bottom plate of the case body 41 in the cylinder hole 52 is defined as a pump chamber 54. The communication hole 66 is formed in the plunger 53.

Since other configurations and operations are the same as those of the first embodiment, common components are denoted by common reference numerals in the drawings, and description thereof is omitted.

[0070]

According to the present invention , a cylinder hole is provided inside.
Pump case and the cylinder hole
Plunger to be inserted and the axis of this plunger
The pump is supported by the pump case and the drive and stop alternate.
Returned stepping motor and this stepping motor
Attached to the output shaft of the
The protruding end also has a large rotating body and the plunger
Penetrate one end in the axial direction in the radial direction, and each end
And is engaged with each radial outer end of the protruding end of the rotating body.
At the same time as the plunger
A movable camshaft and the pump case
This plunger is located radially outward of the plunger.
It is arranged at a radially symmetric position and engages with the cam shaft.
A pair of cam projections, and the
The space closed by the other axial end of the
And the above stepping motor is driven.
The output shaft, rotating body, camshaft, and plunger
To rotate together around the axis,
With the cam shaft and the pair of cam projections
The camshaft moves the plunger in a certain direction in its axial direction.
Reciprocate by roking and expand with the plunger going forward
While pumping liquid into the pump chamber,
The same liquid is supplied from the same pump chamber as
Citea As ejected toward the supply side is, following advantages
It is arising.

That is, first, as described above, the step
The output shaft, rotating body, cam
The axis and the plunger are sequentially linked and shared around the axis.
When the rotor rotates, the radial dimension of the rotating body is large.
Each end of the camshaft is located at each radially outer end of the protruding end.
Each is locked, and therefore,
The locking position of the cam shaft with respect to the rotation center of the rotating body
Both of which are greatly separated from the axis center
The load applied to each other at the joints of the
It is.

Therefore, the stepping motor is driven
Stopping is repeated, and the rotating body and the camshaft are
These joints are subject to repeated loading,
As described above, since this load is reduced to a small extent,
Wear of the joint is suppressed.

Second, as described above, the cam shaft and the cam
The pair of cam projections that match each other is the radial symmetry of the plunger.
Position, so that the camshaft is
At the end side, the cams engage with
It is reciprocated in the axial direction of the axis.

Therefore, the plan is linked with the cam shaft.
When the jaws are reciprocated in their axial direction, the camshaft
Is prevented from prying the plunger.
The plunger pry the inner peripheral surface of the cylinder hole
Is suppressed, and the inner peripheral surface of this cylinder hole is worn.
Is suppressed.

Third, as described above, the camshaft is
It can swing around the penetration to the plunger.
For this reason, if the pair of cam protrusions described above is
There is a small dimensional error.
As a cam engagement of the balance of the cam projection is slightly collapse
Also, the cam shaft swings with respect to the plunger.
This prevents the camshaft from prying the plunger.
Is controlled.

Therefore, also in this point, the plunger is
Squeezing the inner peripheral surface of the cylinder hole is suppressed,
Wear of the inner peripheral surface of this cylinder hole is more reliably suppressed.
You.

According to the first to third functions,
The accuracy of the supply amount of the liquid by the pump is kept good for a long time .

Fourth, as described above, the plunger,
One combination of a stepping motor and a rotating body
The pumps are arranged side by side on
It tends to be large in the direction along the heart.

Therefore, the plunger is moved outward in the radial direction of the plunger.
Because a pair of cam projections that engage with the cam shaft are arranged
And therefore, these cam projections are located along the axis.
In the same direction as the above combination
Is done.

Therefore, when the pump is located along the axis,
Is prevented from becoming large in
It can be made into a compact shape.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a hydraulic pump according to a first embodiment.

FIG. 2 is an overall diagram in the first embodiment.

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 1 in the first embodiment.

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 1 in the first embodiment.

FIG. 5 is a bottom view of the hydraulic pump in the first embodiment.

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 4 in the first embodiment.

FIG. 7 is a map diagram in the first embodiment.

FIG. 8 is a map diagram in the first embodiment.

FIG. 9 is a map diagram in the first embodiment.

FIG. 10 is a diagram corresponding to FIG. 1 in the second embodiment.

FIG. 11 is a sectional view taken along line 11-11 of FIG. 10 in the second embodiment .

[Explanation of symbols]

Reference Signs List 25 lubricating oil (liquid) 27 hydraulic pump (pump) 39 pump case 40 shaft center 50 distributor 52 cylinder hole 53 plunger 54 pump chamber 68 drive mechanism 69 stepping motor 70 output shaft 71 rotating body 73 cam projection 74 cam shaft

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F01M 1/02 F01M 1/16 F01M 1/20 F01M 3/00 F01M 11/00

Claims (1)

(57) [Claims] 1. A pump case having a cylinder hole inside.
A plunger fitted slidably in the cylinder hole in the axial direction, and the pump case on the axis of the plunger.
Stepping supported and alternately driven and stopped
Motor and the output shaft of this stepping motor.
And its protruding end is larger than the radial dimension of its base.
A large rotating body and one end of the plunger in the axial direction
Each end of the rotating body protrudes in the direction
At the outer end of each end in the radial direction,
A cam that can swing about the penetrating part of the lancer
Shaft and diameter of the plunger fixed to the pump case
At the radially symmetric position of this plunger
And a pair of cam projections that
And the axial direction of the plunger in the cylinder hole.
A space closed by the other end to the pump chamber, the scan
By driving the stepping motor, the output shaft, rotating body,
The camshaft and plunger are sequentially interlocked around the axis above.
To rotate together, and with the camshaft accompanying this rotation
The cam shaft with the cam engagement between the pair of cam protrusions is reciprocated at a constant stroke above flop <br/> plunger in the axial direction, the liquid to the pump chamber to expand in forward movement of the plunger while inhaling, liquids dispensing pumps supra liquid from ibid pump chamber to reduce at backward of the same plunger to eject toward the inlet side.