JPS61101685A - Multiple plunger pump - Google Patents

Abstract

PURPOSE:To avoid generation of water hammer upon switching between unload and on-load by a method wherein the switching timing of at least one of respective unloaders is delayed by one period to obtain a slow curve of flow amount variation. CONSTITUTION:Respective cylinders 1 are provided with the unloaders thereof respectively. The unloader 6 is operated in accordance with shifting of a plunger 2 from a delivery stroke to a suction stroke when it is switched to the unloading. When the unload signal is received from a control unit 16, at least one of respective unloaders 6 is operated so as to delay by one period. According to the delay of the operation, the finishing time of unloading is elongated and whereby the change of delivery flow amount may become a slow curve.

Description

[Detailed description of the invention] [Fields of use of Matoujo] This invention uses water S on the discharge side. It won't happen (.

The present invention relates to a multiple plunger pump that can appropriately switch from an on-load state to an unload state and vice versa.

[Conventional technology]

Conventionally, this lumberjack plunger pump has been equipped with an independent suction valve for each cylinder, and the plunger in each cylinder performs the suction and discharge strokes. Some are repeated with a constant phase difference and each intake valve is individually switched to the on-load or unload state by an unloader. In the on-load state, each suction valve opens during the suction stroke of the plunger and closes during the discharge stroke, repeating the opening and closing motion f'l, while in the unload state.

Each suction valve is held open by an unloader. Therefore, in the latter unloaded state, the fluid sucked into the cylinder from the suction valve during the suction stroke is discharged to the suction side through the same suction valve during the discharge stroke. Therefore, at this time, the plunger pump is in the no-load state, and the thief is about to be discharged.The timing of switching from the on-load state to the unload state and vice versa is 3(・There are 8 types of settings, and if the pressure on the discharge Ifj side becomes too steep during the discharge stroke, a problem will occur.

Therefore, in the conventional multi-delay plunger pump, the unloader is switched for each cylinder in the order in which the granger moves from the discharge stroke to the suction stroke, and the switching is carried out during the suction stroke of the plunger in each cylinder. It is set to L5, which ends everything within one round.

In other words, for example, in a plunger pump n4, each plunger in the 1st to nth cylinder or one member of the 1st to nth buds is connected to the suction stroke with a certain phase difference every time the drive shaft of the pump rotates once. When one cycle of the discharge stroke is performed, all the switching in the order of 1st to nth strokes, which transition to the suction stroke, is completed while the drive shaft of the pump is being braked II. In addition.

Numbers 1 to n are numbers corresponding to the order of σ phase shift, with number 1 being the first one that started switching.

Curve A in Fig. 3 represents the change in flow rate when switching from the on-load state to the 7-load state due to the need to change the weight, and the rotation of the drive shaft during this flow tht ratio conversion. Let the angle be 01. In the figure, y, which is represented by a two-dot chain line, and hence curve B, means the solid discharge flow rate of the first to n-th cylinders that are shifted with a certain phase difference, and in the on-load state, these discharge flow rates The sum of these results in a stable miscarriage as shown by curve C up to point P1. In the figure,
Rightmost curve Bf! r: The cylinder that appears is the n4f-th cylinder (V), and the cylinder that shows the n-th curve B to 'EEIIliI is the first one.The plungers in these first to nth cylinders The unloaders are switched in sequence at two points in the suction stroke, resulting in a decreasing change in the flow rate of the curve mA.

By the way, according to the same switching procedure, when switching from the unloading state (fmn) to the on-loading state, contrary to the above case, the curve A is changed from the state (n) with the amount of solder "0" to This results in a stable ripple state as shown by curve C.

[Problem that the invention seeks to solve]

The flow is based on the above-mentioned method for changing the rice! The curve A of change is 5
Figure 443 shows a comparatively old curved image of c5 (This tth first rotation angle θ is small, and the time required for vJ rotation is short.This also means that.

It is a large 4-piece on the discharge side that produces water hammer.

In other words, in order to welcome the water force on the discharge side, the curve of the change in the ruins is drawn as a continuous curve without any localized points, and a gentle curve is drawn. The time spent on switching is relatively small.In this respect, conventional switching systems are not fully satisfactory.
In one.

This invention fully satisfies the above two requirements that are effective in suppressing water hammer.5. The present invention provides a multi-plunger pump that can be used in a variety of ways.

[Means for solving problems]

The multiple plunger pump according to the present invention is used when unloading the suction valve for each cylinder.

The control device for the seventh switching is configured to delay the l71m timing of at least one of each unloader by one period.

[Practical example]

Hereinafter, the explanation will be given based on one example of this invention. Figure 1 shows the pump body and unloader group. It is divided into upper and lower parts. In this example, the pump body is fM as a 9-plunger pump with 9 cylinders 1.
The plunger 2 in each cylinder 1 is connected to a crank 3.

The crank 3 is rotated by a reduction gear 41r and a driving machine 5, and each plunger is reciprocated at equal intervals with a constant phase difference of 40 degrees. Due to this.

Each plunger 2 of 11d performs one cycle of suction stroke and discharge stroke every time the crank 3 rotates once, and the plungers 2 of 11d perform one cycle of operation of the suction stroke and discharge stroke, and are arranged in a continuous manner with a phase difference of 40° for each missing plunger 2 in the suction and discharge strokes. Pick it back.

In detail, there are nine unloaders 6 corresponding to each valley ring 1, and the valley unloaders 6 are as follows:
The suction valve 7 is provided for each cylinder individually. The suction valve 7 is provided at the suction port of the cylinder 1 as shown in FIG. Then, the cylinder fit of this valve seat 8 (, the valve plate 9 that is straightened to the
and? have During the suction stroke, the valve plate 9 automatically surrounds the communication passage 8a due to the negative pressure within the cylinder R, and during the discharge stroke, the valve plate 9 automatically surrounds the communication passage 8a due to the positive pressure within the cylinder R.
T hem. This allows the suction valve 7 to operate as the desired valve +! during normal operation. 4- is Yonago.

The unloader 6 has a spindle 10 that pushes the valve plate 9 from the suction path measurement, and the base end of the spindle 100 is connected to a piston 12 in a cylinder section 11. Cylinder part 11
To the left of the tree, a spring 13 is installed in a compressed state, and in the seventh stone chamber, there are three boats P^, Pa, and Pc.
An inlet pipe 15 for operating air pressure is connected to the solenoid valve 14 and the fire valve. - The magnetic valve 14 can be switched to two states, and in the first switching state, the port 1P person and the PR
Open the gap and apply operating air pressure to the cylinder 8110 stone chamber,! 4
In the second switching state, the gap between the boat Pg and Pc is closed, and the gap between the boats Pg and Pc is opened to release the air pressure in the right chamber of the cylinder section 11 to the outside. The switching state of nt1 corresponds to the on-load KM of the pump. That is, the piston 1 is moved by the air pressure in the right chamber of the cylinder portion 11.
2 is moved to the left against the spring 13, the tip of the spindle 10 retreats to the 8th circle of the valve plate, and d moves the suction valve 7 during normal operation? Don't disturb me. On the other hand, the latter switching state is the unloading state of the pump. That is, by reducing the pressure in the right chamber of the cylinder 11, the piston 12
However, when the spring 130 is activated and the lever changes to the right, the tip of the spindle 10 protrudes from the valve plate 8 and the suction valve 7? A control device 16 is connected to the solenoid valve 14 of each unloader 6, which is forcibly held open. Korikan 0i11 16 has a centimeter 1 that ashes out the 1st movement of the plunger 2 in each cylinder 1.
7 is connected. This centimeter 17 corresponds to the rotational phase of the crank 30, and the rotational phase of the cylinder 1 corresponds to the operating state of the re-plunger 2 in each cylinder 1. Output old code.

111'' The leg device 16 controls the switching of the solenoid valve 14fK of the valley unloader 6 in accordance with the various adjustments from the system in which the pump is incorporated, and the missing part of the centimeter 17n'-etc. Take the timing to switch to the 14th square.

The arrow, the trough caused by the warp control wave ct, 16, and the switching timing of the sea calm valve 14 will be explained.

First, according to the old name of the valley adjustment from the system.

The transition from the on-load state n) to the unload state will be explained below.The timing of the unloader 6 by the magnetic valve 14 will be explained below. This is when the cylinder 1 is in the cylinder 1 and the cylinder 2 is in the suction stroke, and this point is similar to the conventional 17I conversion procedure described above. However, even though the switching timing is different between the two valley unloaders 6, the plunger 2 of the seventh cylinder 1, which corresponds to the first switching unloader 6,
Cylinder 1 which continues to the suction stroke with a phase difference of 40 degrees after the first full stroke (1) If the plunger 2 is set to the second, third, and so on, then the cylinder 1 moves to the suction stroke.
For the unloaders 6 that have been removed in at least one of the 14th to 9th inspections, the corresponding granger 2 moves to the suction stroke, and 7S: the time points are consecutively repeated in the order of numbers 1 and 7. For at least one removed unloader 6, the switch is made at the time point 1 when the corresponding plunger 2 shifts to the other suction stroke delayed by one cycle.

As a result of this switching, the flow change ratio of the song NMD in Figure 3 appears. It is clear from the figure that the curve of the curve (n) is gentler than the curve A due to the changeover of exhausted rice as described above, and the degree of rotation of the crank 3 at the time of the flow change is 0! It's funny. Therefore, the time required for switching is one group or longer. 1 curve L) F (Since there is no point that changes significantly locally, the two female curves mentioned above, which are effective in suppressing the water 84, are adjusted to the light minute.

By the way, the reason why such a melodious song appears is as follows. First of all, if the cylinder l fjz etc. is switched one cycle later than the other, the conventional switching key point 1: If there is another one and the other one will be switched continuously. ', n), etc., (the degree of decrease becomes smaller) of υI1.4t.Furthermore, the switching is delayed by one round and then switches to growth l-) depending on whether the cylinder is 1 or the amount of V conversion.
When switching from unloading down to on-road state according to the Taniha Af layer number of Nstemka et al. In contrast to the above switching case and colleagues, the switching timing for one unloader 6 is delayed by one period from the others. Therefore, in this case, the flow;
In the state 1'l', 1ffl cliff wiping is reversed and n: It becomes a flood state where f is added as shown in table ゎcho at dotsu curve C. This is for the opposite reason to the above case.

The control device Vt16 has a circuit configuration that sets the switching timing based on the electric current from the sensor 17 in order to perform such switching.

S, how many units should delay the switching by one cycle, and should the same number of units be used?
``''C is appropriately set depending on the value phase difference and other formats.This setting cannot be applied to one circuit plane because the control device 16 has a circuit configuration.

[Young fruit of invention]

As explained above, in the multiple plunger pump according to the Ct) invention, when switching the unloader of the suction valve for each cylinder, the control device for the switching σ) A configuration that delays one switching timing by one cycle: Assuming that the white plum of the watershed change at the time of unloader switching is drawn with a gentle curve of 9 strokes, the time ratio required for 7 switchings, Q fishing length (set) Moreover, the flow rate change can be made into a continuous curve with no locally large change points.As a result, the residual water flow on the discharge side can be suppressed to a light minute.

The aim is to avoid the negative effects of the water tower's impact on the disaster victims.

4. Diagram box ν) Explanation: Figure 1 shows the entire example of this invention. This is a diagram to compare the timeliness of the conventional method.

1°°°/linda, 2...plunger, 6...unloader, 16...city IJ+wholesale device, 17...sensor.

Applicant: Ishikawajima Ban, Fusahoe Kadoko, Poor Shi Figure 1 Figure 2 ! Figure 3 −嘱

Claims (1)

[Claims] Each cylinder is equipped with an independent suction valve, and the plunger in each cylinder repeats the suction and discharge strokes with a certain phase difference, and each suction valve is individually on-loaded or unloaded by an unloader. In a multiple plunger pump that can be switched to a different state, a sensor detects the operating state of the plunger in each cylinder, and the timing for switching each intake valve to an on-load state or an unload state is set based on the detection signal of this sensor. and a control device that sequentially switches each unloader in order of the phase shift of the operation of each plunger during the suction stroke of each plunger, and controls switching of at least one of the unloaders during the suction stroke delayed by one cycle. A multiple plunger pump characterized by: