(19)
(11) EP 2 617 469 A2

(12) EUROPEAN PATENT APPLICATION

(43) Date of publication:
24.07.2013 Bulletin 2013/30

(21) Application number: 12003574.6

(22) Date of filing: 08.05.2012
(51) International Patent Classification (IPC): 
A62C 27/00(2006.01)
(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME

(30) Priority: 19.01.2012 KR 20120006244

(71) Applicant: JM motors Co., Ltd.
Samdong-myeon Ulju-gun Ulsan gwangyoksi 689-932 (KR)

(72) Inventor:
  • Kno, Sung-Wang
    Ulju-gun, Ulsan 689-932 (KR)

(74) Representative: Roos, Peter et al
Roospatent Bavariaring 20
80336 München
80336 München (DE)

   


(54) Simple fire truck with easy movement


(57) Provided is a simple fire truck that easily moves to a narrow fire occurred spot difficult for a car to enter by using a transfer wheel driven by a motor separately from a pump driven by an engine, the simple fire truck including: a depressurization groove that is formed between a chamber where a sealing unit receiving pressure of the pump is provided, and a suction hole, so as to depressurize a pressure of the chamber; a lubricating water supply unit for improving durability through lubrication and cooling by supplying lubricating water to an inlet of the chamber according to a vacuum pressure generated during an initial activation of the pump; and a rotor unit having a first protrusion at an end of a side of a rotor provided inside the chamber, and a second protrusion at a periphery of a shaft hole through which a rotation shaft penetrates. Accordingly, the simple fire truck easily moves to the narrow fire occurred spot difficult for a car to enter by using the transfer wheel driven by the motor separately from the pump driven by the engine, prevents a damage of the sealing unit by depressurizing a pressure transferred to the sealing unit by forming a groove between the chamber and a suction unit formed inside the pump, and improves durability of a positive-displacement pump through lubrication and cooling by using a lubricating water suction unit provided at a pump suction unit during an initial activation.




Description

CROSS-REFERENCE TO RELATED PATENT APPLICATION



[0001] This application claims the benefit of Korean Patent Application No. 10-2012-0006244, filed on January 19, 2012, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION


1. Field of the Invention



[0002] The present invention relates to a simple fire truck with easy movement, and more particularly, to a simple fire truck that easily moves to a narrow fire occurred spot difficult for a car to enter by using a transfer wheel driven by a motor separately from a pump driven by an engine, prevents a damage of a sealing unit by depressurizing a pressure transferred to the sealing unit by forming a groove between a chamber and a suction unit formed inside a pump, and improves durability of a positive-displacement pump through lubrication and cooling by using a lubricating water suction unit provided at a pump suction unit during an initial activation.

2. Description of the Related Art



[0003] Generally, when a fire occurs, damage can be remarkably reduced if the fire is quickly handled and extinguished in the easily stage, specifically at a place where huge damage occurs when a fire breaks out, such as a mountain or an open storage yard. It is not easy to put out the fire in the early stage in such a mountain or open storage yard where a fire extinguish equipment is not well prepared, and even if the fire is found early, early extinguishment may be failed due to backwardness and shortage of equipments.

[0004] Specifically, in case of a forest fire generated during a dry period, an extinguish system is activated by mobilizing many manpower to prevent and extinguish a fire. However, the forest fire is not effectively extinguished since very elementary and primitive tools and methods, such as a method of covering the fire with dirt by using a shovel or a pitchfork, are used as firefighting equipments, and only a spray type manual fire extinguisher is used to put out a smoldering fire.

[0005] Similarly, in case of a fire occurred in an open storage yard without water, a narrow alley, a traditional market, or the like, the most important thing is initial extinguishment, but the initial extinguishment is difficult because it is impossible for a fire truck to enter the open storage yard, the narrow alley, the traditional market, or the like.

[0006] Also, a car provided with a separate water tank, and a pump are required since water cannot be supplied to grasses, trees, or the like because the fire truck cannot be directly connected to an outdoor fire hydrant and an OC valve at a park or the like. Accordingly, the present applicant has registered Korean Patent Registration No. 1015060 about a small multipurpose sprinkler truck. However, in Korean Patent Registration No. 1015060, a sealing unit is damaged as a pressure is increased between a chamber and a suction unit, efficiency of a pump is decreased and thus a negligence accident is occurred as a flow rate changes as time passes, and a lifespan of the pump is decreased as durability of a valve and subsidiary apparatus is deteriorated due to a donut phenomenon according to flow resistance.

SUMMARY OF THE INVENTION



[0007] The present invention provides a simple fire truck with easy movement, which easily moves to a narrow fire occurred spot difficult for a car to enter by using a transfer wheel driven by a motor separately from a pump driven by an engine, prevents a damage of a sealing unit by depressurizing a pressure transferred to the sealing unit by forming a groove between a chamber and a suction unit formed inside a pump, and improves durability of a positive-displacement pump through lubrication and cooling by using a lubricating water suction unit provided at a pump suction unit during an initial activation.

[0008] According to an aspect of the present invention, there is provided a simple fire truck that easily moves to a narrow fire occurred spot difficult for a car to enter by using a transfer wheel driven by a motor separately from a pump driven by an engine, the simple fire truck including: a depressurization groove that is formed between a chamber where a sealing unit receiving pressure of the pump is provided, and a suction hole, so as to depressurize a pressure of the chamber; a lubricating water supply unit for improving durability through lubrication and cooling by supplying lubricating water to an inlet of the chamber according to a vacuum pressure generated during an initial activation of the pump; and a rotor unit having a first protrusion at an end of a side of a rotor provided inside the chamber, and a second protrusion at a periphery of a shaft hole through which a rotation shaft penetrates.

[0009] The lubricating water supply unit may include: a lubricating water tank provided to be located above a chamber; a nozzle unit enabling the lubricating water to free-fall according to gravity by being provided at a bottom of the lubricating water tank; a supply valve provided at a top of the housing so as to supply or block the lubricating water to the suction hole; and a filter provided between the lubricating water tank and the nozzle unit.

BRIEF DESCRIPTION OF THE DRAWINGS



[0010] The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:

FIG. 1 is a perspective view showing an overall appearance of a simple fire truck with easy movement, according to an embodiment of the present invention;

FIG. 2 is a view showing a structure for depressurizing a pressure inside a chamber shown in FIG. 1;

FIG. 3 is a magnified view of a portion A of FIG. 2;

FIG. 4 is a graph showing pressures applied to sealing units of a general rotary displacement type pump and of a rotary displacement type pump of the present invention including a groove;

FIG. 5 is a cross-sectional view for explaining an installation structure of a lubricating water supply unit according to an embodiment of the present invention; and

FIG. 6 is a perspective view of a structure of a rotor, according to an embodiment of the present invention.


DETAILED DESCRIPTION OF THE INVENTION



[0011] Hereinafter, the present invention will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. Terms or words used herein should not be interpreted as being limited to common or dictionary meanings, and based on a principle that the inventor can suitably define a concept of a term to describe the invention the best way possible, the terms and words should be interpreted to have meanings and concepts corresponding to the technical aspect of the present invention.

[0012] Exemplary embodiments of the present invention will now be described with reference to accompanying drawings, wherein FIG. 1 is a perspective view showing an overall appearance of a simple fire truck with easy movement, according to an embodiment of the present invention, FIG. 2 is a view showing a structure for depressurizing a pressure inside a chamber shown in FIG. 1, FIG. 3 is a magnified view of a portion A of FIG. 2, FIG. 4 is a graph showing pressures applied to sealing units of a general rotary displacement type pump and of a rotary displacement type pump of the present invention including a groove, FIG. 5 is a cross-sectional view for explaining an installation structure of a lubricating water supply unit according to an embodiment of the present invention, and FIG. 6 is a perspective view of a structure of a rotor, according to an embodiment of the present invention.

[0013] Referring to FIGS. 1 through 6, FIG. 1 is the perspective view of the overall appearance of the simple fire truck with each movement, wherein a brake unit 700 that controls rotation of a transfer wheel 500 driven by receiving power from a motor 400 operated by receiving power of a battery is provided at a plate member 300 on which a pump 200 operated by being connected to an engine 100 that integrally includes a fuel tank and operates the pump 200 by generating power is provided, and a frame member 600 including a handle for steering a direction of the transfer wheel 500 is provided.

[0014] A depressurization groove 200-6 is formed between suction hole 200-1 a and a chamber 200-1 to which a sealing unit 200-5 receiving pressure of the pump 200 is provided, and the depressurization groove 200-6 depressurizes pressure of the chamber 200-1.

[0015] Referring to FIG. 4, a lubricating water supply unit 230 for improving durability through lubrication and cooling by supplying lubricating water according to a vacuum pressure generated during an initial activation of the pump 200 is provided at the suction hole 200-1 a of the chamber 200-1.

[0016] A rotor 220 provided inside the chamber 200-1 has a structure where a first protrusion 220-1 is formed at a side end, and a second protrusion 220-2 is formed at a periphery of a shaft hole through which a rotation shaft penetrates.

[0017] The lubricating water supply unit 230 includes a lubricating water tank 230-1 provided at a top of the chamber 200-1, a nozzle unit 230-2 enabling the lubricating water to free-fall according to gravity by being provided at a bottom of the lubricating water tank 230-1, a supply valve 230-3 provided at the top of the chamber 200-1 to supply or block the lubricating water to the suction hole 200-1a, and a filter 230-4 provided between the lubricating water tank 230-1 and the nozzle unit 230-2.

[0018] The lubricating water tank 230-1 is a storage container for storing predetermined lubricating water, and stores an amount of lubricating water required at least to initially activate the pump 200. Also, since the amount of lubricating water during the initial activation differs according to capacity of the pump 200, the lubricating water tank 230-1 having a suitable size for the capacity of the pump 200 may be provided.

[0019] The nozzle unit 230-2 is provided at the bottom of the lubricating water tank 230-1 so that the lubricating water is discharged outside the lubricating water tank 230-1 by gravity and vacuum pressure in the suction hole 200-1 a. Since an amount of lubricating water during an initial activation of the nozzle unit 230-2 also differs according to the capacity of the pump 200 like the lubricating water tank 230-1, the nozzle unit 230-2 having a suitable discharge amount for the capacity of the pump 200 may be provided.

[0020] When the simple fire truck with easy movement having such a structure according to the present invention is to move to an ignition point or to a point to spray and supply water by using the pump 200, the motor 400 provided at the plate member 300 integrally formed with the frame member 600 is operated to rotate the transfer wheel 500 connected to the motor 400, and the simple fire truck is moved by driving the simple fire truck by using the handle for steering the direction of the transfer wheel 500, and the brake unit 700.

[0021] Once the simple fire truck is moved to the ignition point or the point to supply water, the engine 100 and the pump 200 are operated so as to point the flexible hose toward a direction to spray and supply water, and then water is sprayed and supplied.

[0022] Here, looking at operations of the pump 200, when a fluid is sucked through the suction hole 200-1a via rotation of the rotor 220, the fluid flowed into the chamber 200-1 is compressed via the rotation of the rotor 220 and is instantaneously exploded, and thus the fluid is moved toward a discharge hole at a high pressure.

[0023] The fluid of high pressure gathered at the discharge hole is moved into the chamber 200-1 due to a change of volume inside the chamber 200-1 generated by the rotation of the rotor 220, and then vacuum pressure is applied to the fluid of high pressure below an abrasion plate 200-4.

[0024] When the fluid is discharged as such, lubricating oil may leak as the rotation shaft rotates at a high speed, but such leakage is prevented by the sealing unit 200-5.

[0025] Looking at operations of the sealing unit 200-5, high pressure generated by the rotation of the rotor 220 pressurizes the sealing unit 200-5 by leaking between the abrasion plate 200-4 and the rotation shaft, and the abrasion plate 200-4 formed of a metal is not deformed whereas the sealing unit 200-5 formed of a rubber material is compressed and deformed. When the sealing unit 200-5 is compressed and deformed, removal of the sealing unit 200-5 inside the chamber 200-1 is prevented by the abrasion plate 200-4.

[0026] Since the high pressure transferred to the sealing unit 200-5 is discharged toward the suction hole 200-1a as shown in FIG. 4, the pressure inside the chamber 200-1 to which the sealing unit 200-5 is provided is instantaneously removed.

[0027] As shown in FIG. 4, pressure of about 2.0 ± 0.2 MPa is measured at a point where the sealing unit 200-5 is provided in a conventional rotary displacement type pump where the depressurization groove 200-6 is not formed between the chamber 200-1 and the suction hole 200-1a, but pressure of about 1.2 ± 0.12 MPa is measured in the pump 200 of the present invention. Accordingly, the sealing unit 200-5 usable at maximum pressure of 1.5 MPa, i.e., an inexpensive sealing unit, may be used while considering a safety factor.

[0028] Referring to FIG. 5, in the rotor 220 that transfers the fluid according to gearing of the rotor 220 being rotated, only the first protrusion 220-1 is formed at the side of the rotor 220 in the chamber 220-1 to seal the rotor 220 being rotated and the abrasion plate 200-4. Because the first protrusion 220-1 is formed at an edge of the rotor 220 having a quick circumferential speed, seal force (hermetic force) is decreased when the first protrusion 220-1 is worn away by friction between the abrasion plate 200-4 and the first protrusion 220-1 as the rotor 220 rotates for a long time, and thus it is difficult to maintain airtightness for a long time as high pressure is formed at a shaft sealing member.

[0029] Further, the first protrusion 220-1 and the abrasion plate 200-4 may be damaged as a foreign substance inevitably flowed in during suction of the pump 200 is inserted between the first protrusion 220-1 and the abrasion plate 200-4 while the first protrusion 220-1 rotates. Accordingly, the second protrusion 220-2 is formed near a shaft (a center of a circle) in a circumferential direction besides the first protrusion 220-1, and thus even if the first protrusion 220-1 having a quick circumferential speed is worn away or short-circuited by the foreign substance, the second protrusion 220-2 functions as a sealing member, thereby excellently maintaining seal force.

[0030] The first protrusion 220-1 is directly exposed to the foreign substance flowed into the pump 200 according to the rotation of the rotor 220, and the foreign substance generates a short circuit of the first protrusion 220-1 or abrasion and short circuit of the abrasion plate 200-4 by being inserted between the first protrusion 220-1 and the abrasion plate 200-4 during rotation. Also, the first protrusion 220-1 is relatively quickly worn away than the second protrusion 220-2 since the first protrusion 220-1 has a quick circumferential speed by being disposed at an outermost periphery (edge) in a circumferential direction. However, the second protrusion 220-2 functions as a sealing member for a long time as an abrasion speed of the second protrusion 220-2 is delayed since the second protrusion 220-2 is closer to a rotation center than the first protrusion 220-1, and thus has a relatively slower circumferential speed (1/2 to 1/3 of the first protrusion 220-1).

[0031] Since the foreign substance is not easily led to the second protrusion 220-2, the short circuit of the second protrusion 220-2 is prevented, and thus seal force is improved.

[0032] The lubricating water supply unit 230 is activated before an initial activation of the pump 200. Here, the lubricating water is pre-filled in the lubricating water tank 230-1 before a positive-displacement pump is driven.

[0033] Next, the supply valve 230-3 is opened to activate the positive-displacement pump. Accordingly, vacuum pressure is formed inside, i.e., in a space portion, of the positive-displacement pump according to the rotation of the rotor 220. The vacuum pressure sucks the lubrication water to the suction hole 220-1 a through the nozzle unit 230-2. Then, the lubricating water is continuously supplied from the suction hole 200-1 a to the rotor 220 as shown in a silver line of FIG. 5. At this time, the lubricating water is discharged from the lubricating water tank 230-1 to the suction hole 200-1 a by the vacuum pressure and gravity.

[0034] Meanwhile, the lubricating water is supplied to the space portion along a bottom of the suction hole 200-1 a and sucked between the suction hole 200-1 a and the rotor 220 to function as a priming water. Also, the lubricating water not only prevents pressure in the positive-displacement pump from externally leaking but also cools down frictional heat between the rotor 220 and the space portion.

[0035] The lubricating water supply unit 230 is configured such that a small amount of lubricating water is supplied to a housing by vacuum pressure of an inlet, thereby performing cooling and lubrication between the housing and the rotor 220. Accordingly, durability of the positive-displacement pump is improved.

[0036] The present invention may be used in firefighting equipment for extinguishing fire.

[0037] The simple fire truck with easy movement according to the present invention has following effects.

[0038] First, the simple fire truck can easily move to a small fire occurred spot difficult for a car to enter, by using a transfer wheel driven by using a motor separate from a pump driven by an engine.

[0039] Second, a damage of a sealing unit can be prevented by depressurizing pressure transferred to the sealing unit by forming a groove between a suction unit and a chamber formed inside the pump.

[0040] Third, durability of a positive-displacement pump can be improved through lubrication and cooling by using a lubricating water suction unit provided at a pump suction unit during an initial activation.

[0041] While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.


Claims

1. A simple fire truck that easily moves to a narrow fire occurred spot difficult for a car to enter by using a transfer wheel driven by a motor separately from a pump driven by an engine, the simple fire truck comprising:

a depressurization groove that is formed between a chamber where a sealing unit receiving pressure of the pump is provided, and a suction hole, so as to depressurize a pressure of the chamber;

a lubricating water supply unit for improving durability through lubrication and cooling by supplying lubricating water to an inlet of the chamber according to a vacuum pressure generated during an initial activation of the pump; and

a rotor unit having a first protrusion at an end of a side of a rotor provided inside the chamber, and a second protrusion at a periphery of a shaft hole through which a rotation shaft penetrates.


 
2. The simple fire truck of claim 1, wherein the lubricating water supply unit comprises:

a lubricating water tank provided to be located above a chamber;

a nozzle unit enabling the lubricating water to free-fall according to gravity by being provided at a bottom of the lubricating water tank;

a supply valve provided at a top of the housing so as to supply or block the lubricating water to the suction hole; and

a filter provided between the lubricating water tank and the nozzle unit.


 




Drawing




















Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description