JP5606760B2 - Gas heating equipment - Google Patents

Description

  The present invention provides a PTC element for heating a gas flowing in a case having a cylindrical portion and an end wall portion that closes one end of the cylindrical portion and formed in a bottomed cylindrical shape. The present invention relates to a gas heating device.

  In order to heat the LPG fuel by the heat generated by the PTC element on the upstream side of the regulator for LPG fuel, a cylinder that forms an annular forward path with the case and forms a return path inside the bottomed cylindrical case Patent Document 1 discloses that a PTC element is disposed on the outer surface of a closed end wall of a case.

Japanese Patent Laid-Open No. 11-324813

  However, in the one disclosed in Patent Document 1, when the gas flows through the forward path between the case and the cylindrical member and reverses to the return path side in the cylindrical member, the gas is heated by receiving heat from the PTC element. Thus, it cannot be said that the heat transfer area to the gas is large and the heat transfer efficiency is not high. Moreover, although the specific structure is not indicated by the said patent document 1, although there exists description that a PTC element may be attached to the said cylindrical member, it is that a PTC element is arrange | positioned in a gas passage. It becomes complicated and the structure is not realistic.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a gas heating apparatus having a simple structure capable of efficiently transferring heat from a PTC element to gas flowing through a gas passage. And

In order to achieve the above-mentioned object, the present invention is for heating a gas flowing through a case having a cylindrical portion and an end wall portion that closes one end of the cylindrical portion and formed in a bottomed cylindrical shape. PTC element is disposed on the outer peripheral surface of at least the cylindrical portion and the case, the open end side of the tubular portion from the forward path and the end wall portion side toward the end wall portion side from the opening end side of the tubular portion is inserted into the insertion member is in said case inner formed between the gas passage having a return said tubular portion and said end wall portion towards, the said insertion member, a plurality of first recesses facing the forward, A gas heating device in which a plurality of second recesses facing the return path are formed , wherein the cylindrical portion supports a plurality of flat PTC elements, and a plurality of flat supports In order to form the outer peripheral surface, the cross section is formed in a polygonal shape, the insertion member A central shaft portion disposed in the central portion of the case, and along the one-diameter line of the central shaft portion so as to divide the inside of the cylindrical portion into the forward path and the backward path in cooperation with the central shaft portion. A partition plate portion projecting on both sides from the central shaft portion, and a plurality of flange portions projecting on the outer peripheral surface of the central shaft portion at an interval in the axial direction and coupled to each other by the partition plate portion And the plurality of first recesses between the plurality of flanges facing the forward path, and the plurality of second recesses between the plurality of flanges facing the return path. When the insertion member is inserted into the case, both outer ends in the radial direction of the partition plate portion are formed in a polygonal cross section of the cylindrical portion. The circumferential position of the insertion member in the case is fixed by engaging the corners facing each other. It shall be the first said.

The present invention, in addition to the first feature, the end wall portion other PTC elements to the outer surface of the second, characterized in that it is disposed.

  According to the first feature of the present invention, the gas receives heat from the cylindrical portion side that constitutes a part of the case in both the forward path and the return path of the gas passage, and only inserts the insertion member into the case. With this simple structure, the heat from the PTC element can be efficiently transferred to the gas. The insertion member is formed with a plurality of first recesses facing the forward path and a plurality of second recesses facing the return path, so that the gas flowing in the forward path and the return path between the cylindrical portion and the insertion member is formed. A part of the gas flows into the plurality of first and second recesses on the outer periphery of the insertion member and is temporarily held, and the gas that has flowed into the recesses flows into the gas that does not enter the recesses. In comparison, the temperature of the gas that flows through the forward and return paths also rises because some of the heated gas flows out to the forward and return paths. Performance is improved.

In addition, the forward path and the return path can be formed in the cylindrical portion by the partition plate portion provided in the insertion member, and the forward path and the return path can be easily formed. Further, when the insertion member is inserted into the case, both outer ends of the partition plate portion engage with mutually opposite corner portions of the inner peripheral surface formed in the polygonal cross section of the cylindrical portion. The circumferential position of the insertion member in the case is fixed.

Furthermore, according to the 2nd characteristic of this invention, since gas receives heat not only from the cylinder part of a case but from the end wall part of a case, gas can be heated more effectively.

Vertical sectional view of a pressure reducing valve for LPG fuel to which the present invention is applied 2-2 line enlarged sectional view of FIG. 3-3 enlarged sectional view of FIG. 4-4 enlarged cross-sectional view of FIG. The perspective view which shows the assembly | attachment process of the PTC holding member and PTC element to a case Perspective view of the insertion member Exploded perspective view of PTC heater unit and body Disassembled perspective view of current-carrying member, current-carrying member holding cylinder and cap The perspective view which shows the assembly process of an electricity supply part side assembly The perspective view which shows the assembly process of a PTC heater unit

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  First, in FIG. 1, this pressure reducing valve for LPG fuel is for reducing the pressure of LPG fuel and supplying it to an engine (not shown). A valve mechanism 15 and a diaphragm for opening and closing the valve mechanism 15 are shown. 16.

  The valve housing 21 of the valve mechanism 15 includes a body 17, a gas passage cover member 18 fastened to one surface of the body 17, a heating fluid passage cover member 19 fastened to the other surface of the body 17, A diaphragm cover 22 that includes a valve seat member 20 screwed into the body 17 and sandwiches a peripheral edge portion of the diaphragm 16 with the gas passage cover member 18; and the body 17 and the gas passage cover member. 18 and the heating fluid passage cover member 19 are fastened together by a plurality of bolts 23 and nuts 24.

  The valve mechanism 15 is accommodated in a body 17 and faces a valve chamber 26 that communicates with the high-pressure gas passage 25, and a valve body 29 that can be seated on a valve seat 28 having a valve hole 27 opened at the center thereof; The valve shaft 30 is connected to the diaphragm 16 that operates according to the gas pressure on the downstream side of the valve seat 28 and is connected to the valve body 29.

  The body 17 is provided with a cylindrical portion 17 a disposed at the center of the body 17. One end of the cylindrical portion 17 a is opened to one surface side of the body 17 and the other end is closed by an end wall 32. The bottomed mounting hole 31 is provided in a stepped shape that gradually decreases in diameter toward the end wall 32 side.

  The valve seat member 20 is formed in a cylindrical shape having a flange portion 20a projecting inward in the radial direction at one end, and an annular shape in which a valve hole 27 is opened at the center portion of the flange portion 20a. The valve seat 28 is formed. The valve seat member 20 is screwed into the body 17 to be inserted and fixed in the axial intermediate portion of the mounting hole 31, and the valve seat member 20 is elastically attached to the inner surface of the mounting hole 31 in the axial direction intermediate portion. An annular first seal member 33 that comes into contact is mounted.

  Further, the end wall 32 that closes the other end of the mounting hole 31 has an inner end disposed at a central portion in the cylindrical portion 17a with one end disposed at a position corresponding to the axial middle portion of the valve seat member 20. The other end of the cylindrical portion 17b is integrally connected to the end wall 32 so that a bottomed guide hole 34 having a diameter smaller than the inner diameter of the inner cylindrical portion 17b is coaxially connected to the inner cylindrical portion 17b. Is provided.

  The inner cylindrical portion 17b is fitted with a valve body 29 having a flange 29a projecting radially outward at one end so as to be slidable, and an annular second seal member 35 slidably contacting the outer periphery of the valve body 29. Is mounted on the inner surface near one end of the inner cylindrical portion 17b, and an annular retainer 36 for preventing the second seal member 35 from being detached from the inner cylindrical portion 17b is fitted and fixed to the open end of the inner cylindrical portion 17b. When the portion 29a abuts on the retainer 36, the moving end of the valve body 29 toward the side away from the valve seat 28 is restricted.

  By the way, the valve body 29 is driven in the axial direction by the diaphragm 16. In order to improve the followability of the valve body 29 to the operation of the diaphragm 16, the end wall 32 and the valve in the inner cylindrical portion 17 b. Between the bodies 29, a coiled spring 37 that urges the valve body 29 is contracted on the side where the flange portion 29a is brought close to the valve seat 28. The set load of the spring 37 causes the valve body 29 to It is set to a very small value that allows the diaphragm 16 to follow. An annular third seal member 38 that can be seated on the valve seat 28 is attached to the flange portion 29a.

  An intermediate portion of a valve shaft 30 that passes through the valve body 29 coaxially is coupled to the valve body 29, and one end side of the valve shaft 30 loosely penetrates the valve hole 27 and is connected to the diaphragm 16. The other end of the valve shaft 30 is slidably fitted into the guide hole 34.

  Thus, a valve chamber 26 is formed around the inner cylindrical portion 17b between the valve seat member 20 inserted and fixed in an airtight manner in the middle portion of the cylindrical portion 17a and the end wall 32.

  The gas passage cover member 18 is fastened to the outer peripheral portion of the body 17 so that one end of the cylindrical portion 17a of the body 17 is fitted, and the body 17 and the gas passage for the gas passage are provided inside the cylindrical portion 17a. A decompression chamber 40 communicating with the valve hole 27 is formed between the cover members 18. In addition, a guide cylinder portion 18 a extending coaxially with the valve hole 27 and extending toward the decompression chamber 40 is integrally provided at the central portion of the gas passage cover member 18.

  A diaphragm rod 41 coupled to the center portion of the diaphragm 16 is slidably fitted to the guide tube portion 18a, and an annular first ring is slidably contacted with the inner periphery of the guide tube portion 18a. A four-seal member 42 is mounted, and one end of the valve shaft 30 is connected to the diaphragm rod 41.

  A first retainer 43 is sandwiched between the diaphragm rod 41 and a central portion of one surface of the diaphragm 16, and a shaft portion 41 a provided coaxially with the diaphragm rod 41 includes the diaphragm 16 and the diaphragm 16. By passing through the second retainer 44 that contacts the central portion of the other surface and caulking the shaft portion 41 a to engage with the second retainer 44, the diaphragm rod 41 is placed between the first portion and the center portion of the diaphragm 16. The second retainers 43 and 44 are coupled to the central portion of the diaphragm 16 so as to sandwich the second retainers 43 and 44.

  By the way, a pressure acting chamber 45 is formed between the gas passage cover member 18 and one surface of the diaphragm 16, and a spring chamber 46 is formed between the other surface of the diaphragm 16 and the diaphragm cover 22. Is biased by a coiled diaphragm spring 47 toward the side of reducing the volume of the pressure acting chamber 45, but the spring load of the diaphragm spring 47 can be adjusted.

  An adjustment screw 48 is fitted and supported at the tip of 41a included in the diaphragm rod 41 so as to be rotatable around the axis in the spring chamber 46, and is rotated around the axis coaxial with the rotation axis of the adjustment screw 48. The adjustment screw 48 is screwed onto the inner periphery of a spring receiving member 49 that is engaged with the inner periphery of the diaphragm cover 22 but is allowed to move in the axial direction and is accommodated in the spring chamber 46.

  The diaphragm spring 47 is contracted between the spring receiving member 49 and the diaphragm cover 22, and a tool insertion hole 50 is provided in the diaphragm cover 22 at a position facing the adjustment screw 48, and the tool insertion hole 50 is closed. A cap 51 is attached to the diaphragm cover 22.

  The diaphragm cover 22 is provided with a negative pressure introduction pipe (not shown) that communicates with the spring chamber 46, and a pipe line (not shown) that guides intake negative pressure of the engine to the negative pressure introduction pipe. ) Is connected.

  The body 17 is provided with a circular gas passage groove 52 surrounding the cylindrical portion 17 a provided integrally with the body 17 so as to open on one surface of the body 17, and covers the gas passage groove 52. Thus, the gas passage cover member 18 attached to one surface of the body 17 and the gas passage groove 52 constitute a low pressure gas passage 53, and the body 17 and the gas passage for the outer side of the low pressure gas passage 53. An annular fifth seal member 54 is interposed between the cover members 18.

  Moreover, an opening (not shown) is provided at one place in the circumferential direction of the cylindrical portion 17a so that the decompression chamber 40 formed in the cylindrical portion 17a communicates with the low-pressure gas passage 53. The decompression chamber 40 communicates with the low pressure gas passage 53.

  The LPG fuel that has flowed out of the decompression chamber 40 into the low-pressure gas passage 53 circulates in the low-pressure gas passage 53 so as to make a round around the cylindrical portion 17a. A gas outlet pipe 55 that communicates with the low-pressure gas passage 53 is provided. The gas passage cover member 18 is provided with a relief valve 56 that is inserted into the low-pressure gas passage 53 in the vicinity of the gas outlet pipe 55, and the relief valve 56 is provided in the low-pressure gas passage 53. A valve housing 58 that is formed in a bottomed cylindrical shape having a valve hole 57 that communicates with the tip closing portion and that is provided integrally with the gas passage cover member 18 so as to enter the low-pressure gas passage 53; A valve body 60 that has a seal portion 59 that can close the valve hole 57 at its tip and is slidably fitted to the valve housing 58, and an open end of the valve housing 58 that integrally has a connecting pipe portion 61a. The lid member 61 is fitted and fixed by press-fitting or the like, and the spring 62 is contracted between the lid member 61 and the valve body 60, and the valve body 60 opens the valve hole 57. Release from valve hole 57 in state It is formed to a LPG fuel capable of circulating in the connecting tube portion 61a side.

  Further, a cylindrical portion 64 that enters the low-pressure gas passage 53 so as to form a communication passage 63 for causing the pressure in the low-pressure gas passage 53 to act on the pressure acting chamber 45 facing one surface of the diaphragm 16; The gas passage cover member 18 is integrally provided.

  A heating fluid passage groove 65 is provided on the other surface of the body 17 opposite to the low pressure gas passage 53, and the heating fluid passage is attached to the other surface of the body 17 so as to cover the heating fluid passage groove 65. The heating cover 66 and the heating fluid passage groove 65 form a heating fluid passage 66 adjacent to the high pressure gas passage 25, the valve chamber 26 and the low pressure gas passage 53, and the body 17 is outside the heating fluid passage 66. An annular sixth seal member 67 is interposed between the heating fluid passage cover member 19.

  Engine heating water is introduced into the heating fluid passage 66, and heat from the engine cooling water passes through the body 17 to the LPG fuel flowing through the high pressure gas passage 25, the valve chamber 26 and the low pressure gas passage 53. Communicated.

  Incidentally, the body 17 is provided with an inlet passage 71 that opens to the side surface of the body 17, and the inlet passage 71 is connected to the high-pressure gas passage 25 via a PTC heater unit 72 attached to the side surface of the body 17. Connected to.

  2 to 4, the PTC heater unit 72 has a cylindrical portion 73a and an end wall portion 73b that closes one end of the cylindrical portion 73a, is formed in a bottomed cylindrical shape, and the body 17 A metal case 73 fastened to the side surface of the body 17 and a gas passage 80 connecting the inlet passage 71 and the high-pressure gas passage 25 of the body 17 are inserted into the case 73 so as to be formed between the case 73. And the PTC elements 75, 75,... 76 disposed on at least the outer surface of the cylindrical portion 73a of the outer surface of the case 73, and the PTC elements 75, 75,. And a PTC holding member 77 attached to the case 73, and a current-carrying member 78 connected in common to the PTC elements 75, 75... 76 and the PTC elements 75, 75. The PTC holding member 77 is sandwiched between the case 73 and the energizing portion side assembly 79 covering the case 73. In this embodiment, the PTC elements 75, 75... Are disposed on the outer periphery of the cylindrical portion 73a. The PTC element 76 is disposed on the outer surface of the end wall portion 73b.

  Referring also to FIG. 5, the case 73 includes a cylindrical portion 73a, an end wall portion 73b that closes one end of the cylindrical portion 73a, and a flange portion that protrudes radially outward from the other end of the cylindrical portion 73a. 73c, and the flange portion 73c is fastened to the body 17 with a plurality of, for example, four bolts so that the annular seventh seal member 81 is interposed between the flange portion 73c and the side surface of the body 17. A plurality of, for example, four insertion holes 82, 82... For inserting the bolts are provided in the flange portion 73c.

  The outer peripheral surface of the cylindrical portion 73a has a polygonal shape, for example, a flat plurality of, for example, six support surfaces 83, 83, for contacting and supporting the PTC elements 75, 75, which are flat. A plurality of the PTC elements 75, 75... Arranged on the outer peripheral surface of the cylindrical portion 73a are also formed as a regular hexagon as viewed from the direction along the axis of the cylindrical portion 73a. Will be placed in shape. Further, the outer surface of the end wall portion 73b of the case 73 is also formed as a flat surface so as to contact and support the PTC element 76 having a flat plate shape.

  The PTC holding member 77 surrounds the outer periphery of the end wall portion 73b of the case 73 from the outside in the axial direction and the other end of the cylindrical portion 73a of the case 73 so as to contact the flange portion 73c. A plurality of tabular pieces 6 arranged between the second annular portion 77b in contact with the support surfaces 83, 83... On the outer periphery of the cylindrical portion 73a and connecting the first and second annular portions 77a, 77b. Of the first and second annular portions 77a, 77b between the first and second annular portions 77a, 77b, between the first and second annular portions 77c, 77c,. The rectangular holding holes 84, 84 ... for holding a plurality of PTC elements 75, 75 ... that are in contact with and supported by the support surfaces 83, 83 ... of the 73a are formed, and the first annular portion 77a is an end wall portion. PTC element to be in contact with and supported by the outer surface of 73b 76 to form a rectangular holding holes 85 for holding the.

  Referring also to FIG. 6, the insertion member 74 includes a central shaft portion 74 a that is coaxially disposed at the center portion in the case 73, and a cylindrical portion 73 a in a plane orthogonal to the longitudinal direction thereof. A partition plate portion 74b projecting on both sides from the central shaft portion 74a along one diameter line of the central shaft portion 74a so as to be divided into at least two (two in this embodiment), and the central shaft portion A plurality of flange portions 74c, 74c,... Projecting radially outward from a position spaced apart in the axial direction of 74a.

  By the way, the inner peripheral surface of the cylindrical portion 73a in the case 73 is formed to have a regular hexagonal cross-sectional shape corresponding to the outer peripheral surface, and when the insertion member 74 is inserted into the case 73, In addition, both ends of the partition plate portion 74b are in contact with opposite corner portions of the inner peripheral surface of the cylindrical portion 73a. Among the plurality of flanges 74c, 74c,... Provided in the insertion member 74, the flange 74c that faces the end wall 73b of the case 73 from the inside is opposed to the two of the inner peripheral surfaces of the cylinder 73a that face each other. A positioning protrusion 74d that linearly extends in a direction orthogonal to the partition plate portion 74b so that both ends thereof are in contact with the surface, and a positioning protrusion that contacts and engages a corner portion where one end of the partition plate 74b contacts. 74e. Of the plurality of flanges 74c, 74c, the flange 74c that is closest to the body 17 side is in contact with two surfaces of the inner peripheral surface of the cylindrical portion 73a that the positioning projection 74d abuts on both ends. A pair of positioning projections 74f and 74f that come into contact with each other is provided.

  In this way, the insertion member 74 is inserted into the case 73 with a circumferential position determined, and the gas passage 80 formed between the case 73 and the insertion member 74 is connected to the insertion member. 74, a forward path 80 a from the opening end side of the cylinder part 73 a toward the end wall part 73 b side, and a return path from the end wall part 73 b side to the opening end side of the cylinder part 73 a. It will be divided into 80b.

  Moreover, on the outer periphery of the insertion member 74, there are formed first concave portions 86 facing the forward path 80a and second concave portions 86 facing the return path 80b. Particularly in the present embodiment, the plurality of first recesses 86 are formed between the plurality of flanges 74c, 74c,..., Particularly the flanges 74c facing the forward path 80a, and the return path 80b. The plurality of second recesses 86 are formed between the flanges 74c facing the surface.

  Incidentally, the seventh seal member 81 interposed between the flange portion 73c of the case 73 and the side surface of the body 17 is mounted in a seal groove 87 provided in the side surface of the body 17 in a ring shape having a larger diameter than the cylindrical portion 73a. As shown in FIG. 7, an inlet-side recess 88 that opens the end of the inlet passage 71 and an end of the high-pressure gas passage 25 are formed on the side surface of the body 17 at a portion surrounded by the seal groove 87. An outlet-side concave portion 89 that opens the portion is provided so that the partition wall 90 is interposed between the concave portions 88 and 89.

  The partition wall 90 is disposed corresponding to the partition plate portion 74b of the insertion member 74, and is closest to the body 17 side among the plurality of flanges 74c, 74c... Provided in the insertion member 74. The flange portion 74c includes a contact protrusion 74g that contacts the partition wall 90, and two pairs of protrusions 74h, 74h that are disposed on both sides of the contact protrusion 74g so as to sandwich the partition wall 90 from both sides. And project.

  Thus, when the case 73 having the insertion member 74 inserted therein is fastened to the side surface of the body 17, the insertion member 74 is sandwiched and fixed between the end wall portion 73b of the case 73 and the body 17, and the case 73 and The forward path 80 a of the gas passage 80 formed between the insertion members 74 communicates with the inlet-side recess 88, and the return path 80 b of the gas passage 80 communicates with the outlet-side recess 89.

  Referring also to FIG. 8, the energizing member 78 includes an annular collecting portion 78 a arranged coaxially with the cylindrical portion 73 a outside the end wall portion 73 b of the case 73, and an outer periphery of the collecting portion 78 a. A plurality of first electrode portions 78b, 78b, which extend in the longitudinal direction of the cylindrical portion 73a and which individually and elastically contact a plurality of PTC elements 75, 75 ... disposed on the outer periphery of the cylindrical portion 73a. A second electrode portion 78c extending inward from the inner periphery of the collecting portion 78a and elastically contacting the PTC element 76 disposed on the outer surface of the end wall portion 73b, and a plurality of first electrode portions 78b, 78b..., A terminal portion 78d having one end connected to the collecting portion 78a at the center between a pair of first electrode portions 78b, 78b adjacent to each other and extending radially outward of the collecting portion 78a, Part where the terminal part 78d is disposed The first electrode portion 78b with the exception of, on the outer periphery of the set portion 78a in the middle between 78b ... mutual positioning projections 78e, 78e ... are provided so as to project laterally.

  The energizing member 78 is held by a cylindrical energizing member holding cylinder 91 and a cap 92. The energizing member holding cylinder 91 made of a synthetic resin is formed in a cylindrical shape so as to hold the plurality of first electrode portions 78b, 78b... On the inner peripheral surface. A plurality of positioning notches 93, 93... For fitting the terminal portion 78d and the positioning protrusions 78e, 78e.

  Further, on the inner surface near the other end of the current-carrying member holding cylinder 91, electrode holding parts 91a that abut and support the tips of the first electrode portions 78b, 78b. Are integrally provided with a flange portion 91b projecting outward in the radial direction. Thus, an annular eighth seal member 94 is interposed between the flange portion 91 b of the energizing member holding cylinder 91 surrounding the cylinder portion 73 a of the case 73 and the flange portion 73 c of the case 73.

  The cap 92 made of a synthetic resin is fitted to one axial end portion of the energizing member holding cylinder 91, and protrusions 92 a and 92 a that protrude integrally at a plurality of locations in the circumferential direction of the cap 92. ... and the one end of the energizing member holding cylinder 91 are sandwiched by the collecting portion 78a of the energizing member 78. The cap 92 is integrally provided with an electrode holding portion 92b that abuts and supports the tip of the second electrode portion 78c of the energizing member 78.

  In FIG. 9, the energizing member holding cylinder 91 and the cap 92 are held in a state where the energizing member 78 is held by the energizing member holding cylinder 91 and the cap 92 so that a part of the terminal portion 78d protrudes outward. However, the energizing member 78, the energizing member holding cylinder 91, the cap 92, and the mold portion 95 are formed by being covered with a mold portion 95 made of synthetic resin so that a part of the cap 92 is exposed to the outside. An energization section side assembly 79 is configured. In addition, the mold portion 95 of the energization portion side assembly 79 is integrally formed with a connector portion 95a in which a part of the terminal portion 78d is disposed as a connector terminal, and an eighth seal member is provided on the flange portion 73c of the case 73. A flange portion 95b for coupling with 94 is formed integrally.

  10, in the energizing portion side assembly 79, a plurality of PTC elements 75, 75... Are disposed on the outer periphery of the cylindrical portion 73a, and the PTC elements 76 are disposed on the outer surface of the end wall portion 73b. The cylindrical portion 73a and the PTC holding member 77 that holds the PTC elements 75, 75,.

  Moreover, a pair of metal collars 96, 96 are press-fitted into the flange 73c of the case 73, and screw holes 97, 97 ... are provided in the flange 73c of the case 73 corresponding to the collars 96 ... It is done. Thus, the bolts 98 and 98 inserted through the collars 96 are screwed into the screw holes 97 and tightened, whereby the energized portion side assembly 79 is coupled to the case 73.

  Next, the operation of this embodiment will be described. In the PTC heater unit 72 provided between the inlet passage 71 and the high-pressure gas passage 25 provided in the body 17, the cylindrical portion 73a and one end of the cylindrical portion 73a are closed. LPG fuel circulates in a case 73 having an end wall portion 73b and formed in a bottomed cylindrical shape, and PTC elements 75, 75,..., 76 for heating the LPG fuel are provided on the outer surface of the case 73. Of these, at least on the outer periphery of the cylinder part 73a, the forward path 80a from the opening end side of the cylinder part 73a toward the end wall part 73b and the opening end of the cylinder part 73a from the end wall part 73b side are provided. An insertion member 74 that forms a gas passage 80 having a return path 80 b toward the side between the cylindrical portion 73 a and the end wall portion 73 b of the case 73 is inserted into the case 73.

  Therefore, the LPG fuel receives heat from the cylindrical portion 73a side that forms part of the case 73 in both the forward path 80a and the return path 80b of the gas passage 80, and the outer periphery of the cylindrical portion 73a in the case 73 and the end in the case 73. The heat transfer area for transmitting the heat from the PTC elements 75, 75,... 76 disposed on the outer surface of the wall 73b to the LPG fuel is increased, and the insertion member 74 is simply inserted into the case 73. With the structure, heat from the PTC elements 75, 75... 76 can be efficiently transferred to the LPG fuel.

  Moreover, the insertion member 74 is provided with a partition plate portion 74b that divides the inside of the cylindrical portion 73a into two in a plane orthogonal to the longitudinal direction thereof to form the forward path 80a and the return path 80b. The return path 80b can be easily formed.

  Further, since a plurality of recesses 86, 86... Are formed on the outer periphery of the insertion member 74, a part of the LPG fuel flowing through the forward path 80a and the return path 80b between the cylindrical portion 73a of the case 73 and the insertion member 74 is The LPG fuel flowing into the recesses 86, 86... On the outer periphery of the insertion member 74 is temporarily held, and the LPG fuel flowing into the recesses 86, 86. The temperature rises compared to the fuel, and a part of the heated LPG fuel flows out to the forward path 80a and the backward path 80b, so that the flow of most of the LPG fuel flowing through the forward path 80a and the backward path 80b also rises. Heating performance will be improved.

  Further, since a plurality of PTC elements 75, 75... Are disposed on the outer periphery of the cylindrical portion 73a in the case 73 and the PTC elements 76 are disposed on the outer surface of the end wall portion 73b of the case 73, the LPG fuel is more effectively used. Can be heated.

  Further, a current-carrying member 78 commonly connected to the PTC elements 75, 75,... 76 has an annular gathering portion 78a disposed coaxially with the cylindrical portion 73a outside the end wall portion 73b of the case 73, and A plurality of first electrodes that extend in the longitudinal direction of the cylindrical portion 73a from the outer periphery of the collecting portion 78a and that individually and elastically contact the plurality of PTC elements 75, 75,. .., The second electrode portion 78c extending inward from the inner periphery of the collective portion 78a and elastically contacting the PTC element 76 disposed on the outer surface of the end wall portion 73b, and the collective A terminal part 78d having one end connected to the part 78a is provided, and a current-carrying structure to the plurality of PTC elements 75, 75... 76 can be simplified.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.

  For example, the present invention can be widely applied not only to LPG fuel but also to a gas heating apparatus in which a gas flowing in a case is heated by a PTC element.

73 ... Case 73a ... Cylinder part 73b ... End wall part 74 ... Insertion member 74a ... Center shaft part 74b ... Partition plate part 74c ... Hard part 75,76 ... PTC element 80 ... Gas path 80a ... Outward path 80b ... Return path 83 ... Support surface 86 ... Recess

Claims (2)

A cylinder (73a) and an end wall (73b) that closes one end of the cylinder (73a) are provided to heat the gas flowing in the case (73) formed in a bottomed cylinder. PTC element (75, 76) is disposed on the outer peripheral surface of the at least the cylindrical portion of the casing (73) (73a), the end wall portion from the open end side of the tubular portion (73) (73b) side A gas passage (80) having a forward path (80a) and a return path (80b) from the end wall (73b) side toward the opening end side of the cylinder (73a) is connected to the cylinder (73a) and the end wall. insertion member inner forming between (73b) (74) is inserted into said casing (73), before Symbol in insertion member (74), a plurality of first recesses facing the forward (80a) ( 86), wherein a return path (a plurality of second recesses (86 facing 80b)) is formed A heating apparatus for a gas,
The cylindrical portion (73a) has a polygonal cross section in order to form a plurality of flat support surfaces (83) on the outer peripheral surface for abutting and supporting a plurality of flat PTC elements (75), respectively. Formed into
The insertion member (74) has a central shaft portion (74a) disposed at a central portion in the case (73) and cooperates with the central shaft portion (74a) in the cylindrical portion (73a). A partition plate portion (74b) projecting on both sides from the central shaft portion (74a) along one diameter line of the central shaft portion (74a) so as to be divided into the forward path (80a) and the return path (80b) And a plurality of flanges (74c) that protrude from the outer peripheral surface of the central shaft portion (74a) with an interval in the axial direction and are coupled to each other by the partition plate portion (74b). Have
The plurality of first recesses (86) between the plurality of flanges (74c) facing the forward path (80a) and the plurality of flanges (74c) facing the return path (80b) The plurality of second recesses (86) are respectively formed,
When the insertion member (74) is inserted into the case (73), both outer ends in the radial direction of the partition plate portion (74b) are formed in a polygonal cross section of the cylindrical portion (73a). The gas is characterized in that the circumferential position in the case (73) of the inserted member (74) is fixed by engaging the mutually opposite corners of the inner peripheral surface to be inserted. heating equipment of. The gas heating device according to claim 1, wherein another PTC element (76) is disposed on an outer surface of the end wall (73b).

Images