JP2003028369A - Pipe connection structure and liquid fuel combustion device using the same. - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe connection structure for liquid fuel combustion device, capable of shortening assembling time and preventing leakage of a liquid. SOLUTION: An insert hole 55 is formed in a connection joint 52 fixed on one end side of a pipe 23a, an O-ring 56 is fitted on a projection portion 57 protruding outwardly on the other side of the other pipe 23b at the other side than the projecting portion 57, thereby connecting both of the pipes 23a, 23b in the insert hole of the joint 52. The joint 52 is housed in a holding hole 60 of a holding member 53 and is locked on both sides in a pipe direction. The both of the pipes are elastically clamped by clamping portions 58, 59 of the holding member 53, and the holding member 53 is fixed by the holding member 54, thereby shortening assembling time and preventing leakage of the liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe connecting structure used in a liquid fuel combustion device such as an oil fan heater.

[0002]

2. Description of the Related Art A petroleum fan heater, which is widely used as a heating device for winter in general households and the like, has an oil tank for preliminarily injecting liquid fuel such as kerosene into its main body and a tank below the oil tank. A fuel tank connected to the fuel tank, and a carburetor connected to the oil feeding side of the fuel tank via an oil feeding pipe such as a pipe and an electromagnetic pump for fuel pressure feeding,
And a burner for burning the fuel gas vaporized by the vaporizer.

In the case of a metal pipe used for such a fuel passage, if the pipe passage is long, a method of connecting with a joint in the middle of the pipe is adopted. In this case, as shown in FIG. 8 (a), the pipe 200 on one side is welded to the pipe 200 by welding the male side joint 201 screwed to the outside, and the pipe 202 on the other side is welded to the inner circumference. It is general to employ a structure in which the tip end is subjected to pipe expansion processing 204 via a nut joint 203 whose surface is threaded, and the joint 201 is rotated to tighten the nut 203.

[0004]

By the way, in the structure in which the nut 203 is rotated and tightened like the above-mentioned conventional joint, depending on how the nut 203 is tightened, the seal may be inadequate and may lead to gas or fluid leakage. was there. In addition, the shape of the tip of the metal pipe may be broken when disassembled and repaired, which may lead to liquid leakage during reassembly.

Further, in the structure in which the nut is rotated and tightened on the joint, the processing time in the production line process becomes longer than other processing time, and there is a problem that the processing balance is bad.

In view of these problems, it is an object of the present invention to provide a pipe connection structure in which the assembly processing time is shortened and liquid does not leak.

[0007]

In order to achieve the above object, the present invention forms an insertion hole for inserting another pipe inside a connection joint fixed to one end side of the pipe, A protrusion protruding outward is formed on the end side inserted into the connection joint, and the outer peripheral surface of the pipe and the inside of the insertion hole of the connection joint are located on the side inserted into the connection joint more than the protrusion of the other pipe. By providing a sealing means for sealing the peripheral surface and connecting the both pipes with the insertion hole of the connection joint, the assembly processing time is shortened and the connection without liquid leakage is possible. is there.

In addition to the above connection structure, by providing a disconnection preventing means for preventing the pipes from being disconnected from each other, the disconnection of the pipes can be prevented more reliably.

As the detachment preventing means, a retaining metal fitting which is locked across the retaining projection formed on another pipe and the connecting joint, and a retaining member which retains the connecting joint on both sides in the pipe direction. A holding metal fitting having a hole and having a holding portion for elastically holding the both pipes can be exemplified. In addition, in the case of a holding metal fitting, in addition to the above-mentioned configuration, a fixing metal fitting for fixing the holding metal fitting can be detachably attached.

Further, a structure in which a plurality of insertion holes are formed in the connection joint, a plurality of pipes can be connected to the connection joint, and a plurality of holding portions for elastically holding the plurality of pipes in the holding metal fitting are provided. By doing so, a plurality of pipes can be connected and held at the same time.

Similarly, the holding hole of the holding metal fitting may be set to a size capable of locking a plurality of connection joints, and may have a structure having a plurality of holding portions for elastically holding a plurality of pipes. .

The material of the pipe is not limited to a metal pipe, and may be a synthetic resin pipe, and the holding metal fittings and the fixing metal fittings are not limited to metal but synthetic resin. May be adopted.

The pipe connection structure as described above is suitable for use as a connection structure for the fuel path of the liquid fuel combustion apparatus. For example, a liquid fuel combustion apparatus including a refueling tank detachably attached to the main body and an oil feeding path for feeding fuel from the refueling tank to the combustion section side, or a vaporizer for the combustion section In a liquid fuel combustion device equipped with a return path that returns unburned gas from the
By adopting the above-mentioned pipe connection structure for the oil supply route and / or the return route, fuel leakage can be prevented even if vibration or the like occurs, and the assembly processing time can be shortened, but safety can be improved. An expensive device can be provided.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION (Overall Structure) An embodiment in which the pipe connecting structure according to the present invention is applied to a fuel system pipe of an oil heating equipment will be described below. First, the outline of the oil heating equipment will be described based on FIGS. 1 to 6. FIG. 1 is a perspective view seen from the front of the body of the oil heating equipment, and FIG. 2 is a perspective view seen from the back of the body of the oil heating equipment.

As shown in FIGS. 1 and 2, in this oil heating apparatus, a main body 1 for accommodating a combustion section and a fuel tank.
The exterior part of is formed into a box-shape that is open downward from the front plate 6 that covers the front surface, the side back plate 7 that covers the side surfaces and the back surface, and the upper plate 8 that covers the upper surface. It is placed in.

An air outlet 2 for blowing warm air into the room is formed in the lower portion of the front plate 6, and an operating portion 3 accommodating switches for switching operating states is arranged in the upper portion of the front plate 6. A take-out port 4b (see FIG. 6) of the fuel tank is formed in the upper plate 8, and the tank lid 4 is provided at the take-out port 4b so as to be openable and closable.

On the back side of the side back plate 7, as shown in FIG. 2, a convection fan 9 for sucking air in the room is arranged.
The convection fan 9 is reguarded by a mesh-shaped convection guard 10 to prevent the inhalation of dust.
A temperature sensor 11 that detects the indoor temperature is provided on the back side of the side back plate 7.

FIG. 3 is a schematic diagram showing a liquid fuel combustion apparatus and its fuel path in the oil heating equipment of FIG. This liquid fuel combustion apparatus includes an oil supply tank 12 that is removable from the main body, and an oil supply path B that supplies fuel from the oil supply tank 12 to the carburetor 15 of the combustion unit 25 when the oil supply tank 12 is attached to the main body. The first connecting means 13 for connecting the fuel tank 12 to the fuel passage B on the combustion section side when the fuel tank 12 is mounted on the main body, and the fuel pump for feeding fuel from the fuel tank 12 to the fuel passage B. Interposed electromagnetic pump 14
A vaporizer 15 that heats the fuel from the electromagnetic pump 14 into vaporized gas, and a burner 16 that ejects the vaporized gas of the vaporizer 15 from a nozzle and mixes it with combustion air for combustion.
An air valve 18 as a shutoff valve for sending air to the oil feeding path B to shut off the supply of fuel to the electromagnetic pump 14 side, and a carburetor 15
Return path C for returning unburned gas from the tank to the refueling tank 12 side
And a second connecting means 17 for connecting the fuel tank 12 to the return path C on the combustion section 25 side when the fuel tank 12 is attached to the main body.

The refueling tank 12 has a refueling port 44 at the upper portion thereof, and the refueling port 44 is closed by a closing means 19 such as a refueling cap.
It is closed by and can be accommodated in the tank accommodating chamber 4a with the refueling port 44 facing upward. Then, the fuel from the refueling tank 12 is connected to the first connecting means 13
Oil is directly sent to the combustion section 25 side via
The unburned gas from the vaporizer 15 can be returned to the refueling tank 12 via the second connecting means 17.

The oil supply path B on the combustion section side is a copper pipe 21 for connecting the first connecting means 13 and the electromagnetic pump 14,
Copper-based pipe 2 for connecting the electromagnetic pump 14 and the vaporizer 15
2 and. In the return path C, the carburetor 15 and the second
It is provided with a copper-based pipe 23 for connecting with the connecting means 17 of the above. Since this pipe 23 has a long path as described later,
The pipe connection structure according to the present invention is adopted.

FIG. 4 is a state view in which the front plate side of the main body of FIG. 1 is partially cut, FIG. 5 is a side sectional view of the main body combustion section, and FIG. As shown in the figure, the main body 1
When viewed from the front, the combustion section 25 is arranged on the left side, and the fuel tank 12 and the electromagnetic pump 14 are arranged on the right side. Body 1
On the left side of the combustion unit 25, a combustion unit 25 incorporating the burner 16 and the carburetor 15 is provided, a combustion unit frame 26 that surrounds the periphery of the combustion unit 25, and a combustion unit frame front 27 that covers the upper front portion of the combustion unit frame 26. ing.

The combustion section 25 includes a carburetor 15 and a burner 16
A burner box 28 for housing the burner 16, a burner partition plate 29 for fixing the burner box 28, and a combustion chamber 30 surrounding the flame of the burner 16.

The carburetor 15 vaporizes the liquid fuel sent from the electromagnetic pump 14 by a vaporization element to make the solenoid valve 3
The vaporized fuel can be vigorously ejected to the burner 16 side from the nozzle 31 whose opening and closing is controlled by 3. Further, the unburned gas accumulated in the vaporizer 15 due to the blockage of the nozzle of the vaporizer 15 is returned to the fuel tank 12 through the pipe 23.

The burner 16 mixes the combustion gas vaporized by the vaporizer 15 with the primary combustion air and burns the mixed combustion gas at the flame port 16a. The burner box 28 has a box shape that is open at the top and can accommodate the burner 16. The mixing pipe of the burner 16 is attached to the bottom side, and the ignition heater 35 and the frame sensor 36 are attached to the side faces. Has become. A burner cover 37 is attached to the lower surface of the burner box 28, and the sound absorbing / insulating material attached to the inner side prevents absorption of combustion noise and a decrease in temperature of the burner itself.

First connecting means 13 and second connecting means 17
As shown in FIGS. 17 to 20, each has a structure in which it is separated into a connection joint portion on the fuel tank side and a connection joint receiving portion on the combustion portion side.
On the second side, both connection joints 13a, 17a of the first and second connecting means 13, 17 are integrated to form a joint portion 47, and on the combustion side, the first and second connecting means 13, 17 connection joint receiver 13
The joint receiving portion 100 is configured by integrating b and 17b into a compact structure. The details will be described later.

As shown in FIG. 6, a substantially rectangular tank housing chamber 4a surrounded by a tank guide 41 is arranged on the right side of the main body, and a rectangular parallelepiped is formed by cutting and raising a part of the tank guide 41 at the right corner. The tank guide fixing member 42 is attached, and the electromagnetic pump 14 is attached to the lower portion of the fixing member 42.

The return pipe 23 is a pipe connecting the carburetor 15 to the connection joint receiver 17b on the return path side of the joint receiving portion 100. As shown in FIGS. 4 and 7, the path connects the left and right sides of the main body. Since it is long, the connecting portion 51 is provided on the way.

The connecting portion 51 includes a connecting joint 52, a holding metal fitting 53, and a fixing metal fitting 54, and the divided pipe 23.
The a and 23b can be connected to each other in the tube axis direction.

(Structure of Pipe Connection Portion) FIG. 7 is a piping route diagram to the carburetor and the connection joint receiving portion, and FIGS. 8 (a) and 8 (b).
3A and 3B respectively show cross-sectional views of a conventional pipe connection structure and the present invention. 9 is an exploded perspective view showing the pipe connection / holding structure, FIG. 10 is a side view showing the pipe holding structure using the holding metal fittings, FIG. 11 is a front view showing the same, and FIG. 12 is a side view showing the pipe fixing structure using the fixing metal fittings. 13 is a front view thereof.

As shown in FIG. 8B, the connection joint 52
Is formed into a tubular shape, and one end of one pipe 23a (for example, a joint side pipe) is inserted from one side of the insertion hole 55 at the center thereof and fixed by welding or the like. On the other end side of the insertion hole 55, a large diameter hole portion 55a into which the O-ring 56 and the protruding portion 57 of the other pipe 23b (for example, vaporizer side pipe) described later can be fitted is formed.

On the other end of the other pipe 23b, there is a protruding portion 57 that protrudes outward in the radial direction at a portion of a predetermined length from the edge on the other end side.
Is formed, an O-ring 56 as a sealing means is fitted to the end face side of the projecting portion 57, and the other metal tube 23b can be fitted into the insertion hole 55 of the connection joint 52.
The annular O-ring 56 and the protrusion 57 can be fitted in the large diameter hole 55a in a watertight state. Protrusion 57
Is formed by stringing (beading) the pipe 23b, but it may be formed by another method.

As shown in FIG. 8B, the O-ring 56 has a step portion 55 between the outer peripheral surface of the other pipe 23b and the large-diameter hole portion 55a of the insertion hole 55 of the connection joint 52 and the insertion hole 55.
It is possible to prevent the liquid from leaking from the connecting portion of the pipes 23a and 23b by elastically contacting b.

The retaining metal fitting 53 and the fixing metal fitting 54 are provided as detachment preventing means for preventing the pipes 23a and 23b from coming out of each other. Holding bracket 5
3, two sets of clamping parts 58, 59 for elastically clamping the ends of both pipes 23a, 23b to be connected are arranged at predetermined intervals in the piping direction.
The predetermined interval between the nine is set to be slightly larger than the length of the connection joint 52 in the piping direction, and the inner ends of the holding portions 58 and 59 regulate the movement of the connection joint 52 in the piping direction.
That is, the space between the sandwiching portions 58 and 59 is the connecting joint 52.
Retaining hole 60 that allows the interposition of
It is supposed to function as.

The sandwiching portions 58 and 59 are semi-arcuate curved portions projecting outward at the intermediate portions of a pair of elastic holding pieces 61 and 62 which are arranged to face each other in the front-rear direction orthogonal to the piping direction. By forming the, the function can be achieved.

As the fixing metal fitting 54, a plate material or the like may be used which locks the pair of holding pieces 61, 62 constituting the holding portions 58, 59 in a direction in which they approach each other.

As shown in FIG. 9, the holding metal fitting 53 of the present embodiment is formed by pressing a single elastic metal plate, and sandwiching portions 58 and 59 on both left and right sides thereof, and a holding hole at the center thereof. 60 is formed. That is, the holding metal fitting 53 has a shape in which a single elastic metal plate is bent into a substantially U shape in a side view (as viewed from the piping direction), and an open portion 65 at the tip thereof is spread outward in an inverted C shape. In the middle of the vertical side, semicircular holding portions 58 and 59 protruding outward are formed to hold the pipes 23a and 23b, and the U-shaped bottom portion is formed wide.

In the center of both side surfaces of the holding metal fitting 53, a holding hole 60 in the shape of a square hole is formed so as to accommodate the connection joint 52 and reaches an opening portion 65 having an inverted C-shape.
In the upper side of the holding hole 60, a cutout hole 66 for attaching the fixing fitting 54 is continuously formed. This holding hole 60
Left and right sides of the holding piece 61 forming the holding portions 58, 59,
62.

The left-right width (length in the piping direction) of the holding hole 60 is
The size is set to be slightly larger than the right and left length of the connection joint 52, and the movement of the connection joint 52 in the piping direction can be restricted by the inner edge of the holding hole 60.

Further, the cut-and-raised portion cut and raised from the metal plate to form the holding hole 60 is set flush with the U-shaped bottom portion to form a pedestal 68, and the main body is placed on the pedestal 68. A mounting hole 67 for mounting on the stand 5 is formed.

The fixing metal fitting 54 is formed by bending a metal plate material into a pentagonal shape having a mountain-shaped cross section in order to prevent the tip end opening portion 65 of the holding metal fitting 53 from expanding, and the second corner portion 54a and the fourth corner portion 54 are bent.
The tip of the open portion 65 is locked at the inner corner of b, and the locking piece 54d is bent horizontally from one end (first corner) to the inside so that the locked state with the holding metal fitting 53 is kept good. And the removal claw 5 at an obtuse angle from the other end (fifth corner) to the outside.
4e is bent so that the fixing metal fitting 54 can be easily attached and detached.

In the assembling procedure of the pipe connecting portion 51 in the above structure, first, the O-ring 56 is inserted into the protruding portion 57 of the vaporizer side pipe 23b, and the pipe 23a on the joint receiving 17b side is inserted.
The pipe 23b on the carburetor side is inserted into the inner large-diameter hole 55a of the joint 52 of FIG.
3a and 23b are connected.

Next, as shown in FIGS. 10 and 11, the joint 52 is inserted into the holding hole 60 of the holding metal fitting 53, and the pipes 23a and 23b on both sides have a semicircular cross section of the holding portion 5.
Insert by pressing down until it fits in 8,59. Finally, as shown in FIGS. 12 and 13, the locking piece 54d on the inner side of one end of the fixing metal fitting 54 is attached to the notch hole 66 of the holding metal fitting 53.
Then, the other end is hooked and fixed to the open portion 65 of the holding metal fitting 53.

Then, the pipes 23a and 23b are elastically clamped by the pair of clamping portions 58 and 59, respectively, and the joint 52 is in a state in which the left and right edges of the holding hole 60 are restricted from moving in the pipe direction. There is.

Therefore, even if the pipe joint 52 is vibrated or pulled by hand, the pipes 23a and 23b can be prevented from coming off,
Further, even if the pipes 23a and 23b are pulled in the left-right direction, the pipes 23a and 23b do not come off and the fuel can be prevented from leaking from the connection portion 51.

Further, since the holding metal fitting 53 is prevented from spreading by the fixing metal fitting 54, the connection between the pipes 23a and 23b is firmly held. Further, since the pipe joint structure is also simplified, it is easier to assemble than the connecting work by the nut rotation method shown in FIG. 8A, and the assembling time can be greatly shortened.

In the above embodiment, the joint structure is adopted only in the pipe 23 of the return path C. However, if the pipe 22 from the electromagnetic pump 14 to the carburetor 15 becomes longer, the pipe 22 is connected in the middle thereof. It is also possible to provide the portion 51 and connect the plurality of pipes 22 and 23 of the oil feed route B and the return route C to each other.

FIG. 14 shows that the joint 52 has a plurality of insertion holes.
It is a side view which shows a structure which can connect several piping with one joint 52. The joint 52 of this form is formed in a flat elliptical shape in a side view, and has two insertion holes for connection of the return path pipe 23 and an insertion hole for connection of the oil supply pipe 22 formed at the upper and lower sides thereof. There is.

On the other hand, the holding metal fitting 53 is used for the return path pipe 2.
3 and the oil supply route pipe 22 in order to elastically clamp them, the return route pipe clamping portions 58 and 59 are provided.
And the sandwiching portions 72, 73 of the oil supply path pipe 22 are formed in upper and lower two stages. Each holding part 58, 59 and 72, 73
The respective intervals are set to be slightly larger than the length of the joint 52 in the piping direction, and the holding holes 60 between the sandwiching portions regulate the movement of the joint in the piping direction. Other configurations are similar to those of the embodiment shown in FIGS. 7 to 13.

In the above construction, first, the connecting portion of the pipe 22 on the oil feeding path side is inserted into the lower insertion hole of the joint 52,
Next, the connection portion of the pipe 23 of the return path is inserted into the upper insertion hole 55 of the joint 52, and the joint 52 is held by the holding metal fitting 53.
It may be inserted into the holding hole 60, and then the fixing metal fitting 54 is attached to connect the pipes.

FIG. 15 is a side view showing a structure in which a plurality of pipes can be connected by using a plurality of joints 52 and 75. In this embodiment, a joint 52 for return path piping having a structure similar to that of the joint 52 shown in FIG. 8B and a joint 75 for oil supply path piping are arranged in two upper and lower stages. Also, holding metal fittings 5
The holding hole 60 of No. 3 is set to a size capable of locking the upper and lower connecting joints 52 and 75, and the holding metal fitting 53 elastically connects the plurality of pipes 22 and 23 to each other similarly to the embodiment shown in FIG. It is provided with upper and lower two-stage sandwiching portions 58, 59 and 72, 73 which are sandwiched between.

Also in the above-mentioned configuration, as in the embodiment shown in FIG. 14, the connection portion of the pipe 22 on the oil supply route side and the connection portion of the pipe 23 on the return route can be held and fixed.

(Structure of Connection Means) FIG. 17 is a schematic view of an oil feeding side joint and its joint receiver when the tank is inserted into the body, and FIG. 18 is an outline of the oil feeding side joint and the joint receiver when the tank body is mounted. FIG. 19 is a schematic view of the return oil side joint and its joint receiver when the tank is inserted into the main body, and FIG. 20 is a schematic view of the return oil side joint and the joint receiver when the tank main body is attached.

As shown in the figure, the tank side connection joint portion 47 is formed by integrating the oil supply route side connection joint 13a and the return route side connection joint 17a. Each of the connection joints 13a and 17a has a tubular joint body 80, a valve mechanism 81 incorporated therein, and a valve that doubles as a spring receiver of the valve mechanism 81 by closing the upper end opening of the tubular body of the joint body 80. It is provided with a presser 82, and the base end side flanges 80d of the respective main bodies 80 are connected and integrated with each other. This connection joint part 47 is
It is arranged at the front right corner of the side surface of the fuel tank 12.

The valve mechanism 81 is a tubular joint body 80.
A substantially conical valve body 83 for opening and closing the lower end opening of the valve body, an O-ring 84 attached to the conical portion of the valve body 83 and elastically contacting the closing surface of the main body 80, and for urging the valve body 83 in the valve closing direction. And a valve body spring 85 interposed between the head of the valve body 83 and the valve retainer 82.

This valve mechanism 81 has a valve body 8 when the tank is mounted.
3 contacts the joint receivers 13b and 17b and is pushed upward to open the valve so that the oil supply path B and the return path C of the fuel tank 12 are in communication with each other, and when the tank 12 is detached from the main body, the valve spring 85 The valve body 83 is seated on the closing surface of the joint body 80 by the urging force of the valve body to close the valve body.

Further, each joint body 80 is provided with a passage communicating with the fuel tank 12 side, and the inner ends of the suction pipe 20 and the return pipe 24 are communicated with each passage.

On the other hand, the joint receiving portion 100 on the combustion portion side facing the joint portion 47 has a receiving main body 98 fixed to the upper surface of the tank guide fixing member 42 with a screw, and an oil feeding side provided in parallel with the receiving main body. The joint receiver 13b and the joint receiver 17b on the return oil side, and the air valve 18 arranged in the receiver body 98b are provided.

As shown in FIGS. 17 and 18, the oil-sending-side joint receiver 13b is a rod-shaped valve receiver 98a protruding upward from the central position of the recess formed in the upper surface of the receiver body 98.
In order to cover and seal the periphery of the valve receiver 98a at the time of connecting the oil feeding joint 13a, a substantially cylindrical connecting packing 102 placed on the upper surface of the receiving main body 98, and a sealing property covering the circumference of this packing. The packing 10 in order to improve the oil flow and to perform the guide function of the oil sending side joint 13a.
2 is provided with a substantially cylindrical packing retainer 103 for fixing the lower end flange of 2 to the upper surface of the main body 98 with a screw, and when connecting the oil sending side joint 13a, the oil sending side joint 13
The valve element 59 of a is pushed by the valve seat 98a to open the valve.

An annular groove 98b is formed around the valve support 98a.
Is formed, and a horizontal passage 98c that communicates with the pipe 21 from the groove portion 98b to the electromagnetic pump 14 side is formed. A rising passage 98d is provided in the middle of the passage 98c, and the passage 98d is connected with the outlet of the air valve 18 in an open state.

As shown in FIG. 3, the air valve 18 is for taking air from the outside of the oil supply path B from the oil supply tank 12 to the electromagnetic pump 14 and shutting off the fuel supply of the oil supply path. . The opening / closing operation of the air valve 18 is performed by the opening / closing operation of the built-in solenoid valve 18a.

The joint receiver 17b on the return oil side is shown in FIG.
As shown in FIG. 9 and FIG. 20, the valve mechanism 105 is housed in the lower valve chamber of the valve hole 98e formed in the upper surface of the receiving main body 98, and the passage 98f is formed in the horizontal direction on the side surface of the valve chamber. The body 98 has a first connection joint receiver 13
Similar to b, the connection packing 102 and the packing retainer 103 are fixed around it.

The valve mechanism 105 includes a receiving valve body 106 that opens and closes the valve hole 98e, a receiving valve body cap 108 that closes the lower portion of the valve chamber, and the cap and the receiving valve body 106.
And a O-ring 109 fitted to the closing surface of the receiving valve body.

In the above structure, the valve body 83 of the connection joint 13a is pushed by the valve retainer 98a of the connection joint receiver 13b to be opened when the fuel tank is attached.
When the electromagnetic pump 14 is driven in this state, the fuel tank 1
The fuel in 2 is sucked in from the suction pipe 20, passes through the inside of the connection joint 13, passes through the passages 98c, 98d, and then the pipe 2
1 to the vaporizer 15 via the electromagnetic pump 14.

On the other hand, between the joint 17a on the return path side and the joint receiver 17b, when the valve body 83 of the joint 17a on the return oil side pushes the receiving valve body 106 by mounting the refueling tank 12, first, the receiving valve body 106 is received. Is pushed downward to open the valve, and then, after the receiving valve body 106 reaches the lowermost position, the receiving valve body 106 is reversely pushed to open the valve body 83.

As a result, when the electromagnetic pump 14 is stopped at the time of extinguishing or igniting, the combustion gas remaining inside the carburetor or in the path passes through the return pipe 23 and the second connection joint 17 to refuel from the return pipe 24. Since it returns to the tank 12, it is possible to reduce combustibility and odor during extinguishing or ignition.

FIG. 16 (a) is a front sectional view showing another embodiment of the detachment preventing means, and FIG. 16 (b) is a perspective view of the retaining metal. In the pipe connection structure of the present embodiment, as shown in the drawing, a retaining projection 76 (stringing portion) is formed on the other pipe 23b closer to the center of the pipe than the protrusion 57 for locking the O-ring 56. Further, a ring-shaped concave groove 77 is formed on the outer peripheral surface of the connection joint 52, and the protrusion 7 for preventing the slip-off is formed.
6 is provided so as to be locked across 6 and the concave groove 77 of the connection joint 52 to prevent the other pipe 23b from coming out in the pipe direction.

As shown in FIG. 16 (b), the retaining metal fitting 78 includes a metal fitting body 78a formed in a semi-cylindrical shape and C-shaped locking pieces 78b, 78 formed on both sides in the piping direction.
c and a pair of joint guide wing pieces 78d formed on both sides in the circumferential direction of the metal fitting body 78a and set in an inverted V shape in a side view. Of the locking pieces 78b, 78c on both sides of the main body, the inner diameter of one locking piece 78b is the vaporizer side pipe 23b.
Is set to be slightly larger than the pipe diameter, and the retaining projections 76 are prevented from moving toward the carburetor side (the center side of the pipe) inside the pipe direction. Further, the inner diameter of the other locking piece 78c is set to be slightly larger than the groove bottom diameter of the connection joint 52 so as to regulate the movement of the concave groove 77 in the piping direction. Other connection structures for the pipes 23a and 23b are similar to those of the embodiment shown in FIG. 8 (b).

In the above structure, to connect the vaporizer side pipe 23b and the joint receiving 17b side pipe 23a,
The O-ring 56 is inserted into the protruding portion 57 of the carburetor-side pipe 23b, and the carburetor-side pipe 23b is inserted into the inner large-diameter hole 55a of the joint 52 of the joint receiver 17b-side pipe 23a through the O-ring 56. Up to both pipes 23a, 23b
Connect.

Next, the fitting 52 is covered with a retaining metal fitting 78 on the outer peripheral surface of the connection fitting 52 from a direction orthogonal to the piping direction,
The locking piece 78b on one side is locked to the protruding portion 76 exposed from the joint 52, and the locking piece 78c on the other side is connected to the connecting joint 52.
If it is locked in the groove 77 on the outer peripheral surface of the carburetor side pipe 2
3b can be prevented from coming off. At this time, the retaining metal fitting 7
Both guide vanes 78d of No. 8 are guided while abutting on the peripheral surface of the connection joint 52. In addition, the pipes 23a and 23b
When separating, the guide wing piece 78d expanded in an inverted V shape.
The retaining metal fitting 78 can be removed from the connection joint 52 by holding.

The present invention is not limited to the above embodiment, and many modifications and changes can be made within the scope of the present invention. For example, in the above-described embodiment, the present invention is applied to the connecting portion of the pipe of the route for feeding or returning the fuel between the refueling tank and the combustion unit, but the present invention is not limited to this, and the fuel fixed to the lower side of the refueling tank is used. In a liquid combustion apparatus including a tank, it can be applied as a connecting structure of a pipe connecting a fuel tank and a carburetor. Furthermore, it goes without saying that the present invention can be applied not only to the pipe connection structure of the liquid fuel combustion apparatus but also to the connection structure of other pipes.

[0071]

As is apparent from the above description, according to the present invention, the joint of the pipe does not come off even if it is vibrated or pulled by hand, and it does not come off even if the pipe is pulled in the left-right direction. There is no fuel leakage from the section.

[Brief description of drawings]

FIG. 1 is a perspective view of the oil heating device as viewed from the front of the main body.

[Fig. 2] Similarly, a perspective view of the oil heating device as viewed from the rear of the main body.

FIG. 3 is a schematic diagram showing a liquid fuel combustion apparatus and its fuel path in the oil heating apparatus of FIG.

FIG. 4 is a state diagram in which the front plate side of the main body of FIG. 1 is partially cut.

FIG. 5 is a side sectional view of a main body combustion section.

FIG. 6 is a plan view of a fuel tank storage chamber

[Fig.7] Piping route diagram to carburetor and connection joint receiving part

FIG. 8A is a cross-sectional view showing a conventional pipe connection structure,
(B) is sectional drawing which shows the piping connection structure which concerns on this invention.

FIG. 9 is an exploded perspective view showing a pipe connection / holding structure according to the present invention.

FIG. 10 is a side view showing a pipe holding structure similarly using a holding metal fitting.

11 is a front view of FIG.

FIG. 12 is a side view showing a pipe fixing structure using fixing brackets.

FIG. 13 is a front view of FIG.

FIG. 14 is a side view showing an embodiment of a pipe connection structure capable of connecting a plurality of pipes.

FIG. 15 is a side view showing another embodiment of a pipe connection structure capable of connecting a plurality of pipes.

16 (a) is a front sectional view showing another embodiment of the detachment preventing means, and FIG. 16 (b) is a perspective view of the retaining metal fitting.

FIG. 17 is a schematic view of an oil sending side joint and its joint receiver when the tank is inserted into the main body.

FIG. 18 is a schematic diagram of an oil-sending side joint and its joint receiver when the tank body is mounted.

FIG. 19 is a schematic view of a return oil side joint and its joint receiver when the tank is inserted into the main body.

FIG. 20 is a schematic view of the return oil side joint and its joint receiver when the tank body is mounted.

[Explanation of symbols]

1 body 2 outlet 3 operation part 4 tank lid 5 table 6 front plate 7 side back plate 8 Upper plate 9 Convection fan 10 Convection guard 11 Temperature sensor 12 Refueling tank 13 First connection means 14 Oil pump (electromagnetic pump) 15 vaporizer 16 burners 17 Second connection means 18 Shut-off valve (air valve) 21,22 piping 23 Branch piping 24 Return piping 25 Combustion part 26 Burning part frame 28 burner box 30 combustion chamber 41 Tank guide 42 Tank guide fixing member 51 Pipe connection 52 Connection joint 53 Holding bracket 54 Fixing bracket 60 holding hole

Continued front page    F-term (reference) 3H016 CA04                 3J106 AA01 AA04 AB01 BA01 BB01                       BC04 BD01 BE01 BE12 BE22                       BE29 BE30 BE33 CA07 EB02                       EB05 EB08 EB11 EC01 EC07                       ED03 ED05 ED14 ED43 EE01                       EE13 EF04 EF15                 3K068 AA15 CA05 CA07 CB03 DA01

Claims (8)

[Claims] 1. A projection, which is formed inside a connection joint fixed to one end of a pipe, has an insertion hole into which another pipe is inserted, and which projects outward toward an end inserted into the connection joint of the other pipe. A portion is formed, and a sealing means for sealing the outer peripheral surface of the pipe and the inner peripheral surface of the insertion hole of the connection joint is provided on the side inserted into the connection joint with respect to the protruding portion of the other pipe, and the both pipes are A pipe connection structure characterized in that the pipes are connected at an insertion hole of the connection joint. 2. The pipe connecting structure according to claim 1, further comprising disconnection preventing means for preventing the pipes from being disconnected from each other. 3. The retaining means has retaining holes for retaining the connection joint on both side surfaces in the pipe direction, and a retaining portion for elastically clamping the end portions of the both pipes. The pipe connection structure according to claim 2, wherein the pipe connection structure comprises a metal fitting. 4. The pipe connecting structure according to claim 3, wherein a fixing metal fitting for fixing the holding metal fitting is detachably attached to the disconnection preventing means. 5. The connecting joint has a plurality of insertion holes and has a structure capable of connecting a plurality of pipes, and the holding metal fitting includes a plurality of holding portions for elastically holding the plurality of pipes. Item 5. The pipe connection structure according to any one of items 1 to 4. 6. The holding hole of the holding metal fitting is set to a size capable of locking a plurality of connection joints, and the holding metal fitting includes a plurality of holding portions for elastically holding a plurality of pipes. Item 5. The pipe connection structure according to any one of items 1 to 4. 7. An oil supply tank detachably mounted on the main body, and an oil supply path for supplying fuel from the oil supply tank to the combustion section side, wherein the oil supply path includes any one of claims 1 to 6. A liquid fuel combustion apparatus characterized by adopting the pipe connection structure described in (1). 8. A refueling tank removably attached to the main body, a refueling path for refueling fuel from the refueling tank to the combustion section side, and a refueling tank for unburned gas from the carburetor of the combustion section. A return path for returning to the side, and the pipe connection structure according to any one of claims 1 to 6 is adopted for the return oil path.