JP4451407B2

JP4451407B2 - Bidirectional constant pressure expansion valve

Info

Publication number: JP4451407B2
Application number: JP2006047910A
Authority: JP
Inventors: 聡藤本
Original assignee: Pacific Industrial Co Ltd
Current assignee: Pacific Industrial Co Ltd
Priority date: 2005-07-22
Filing date: 2006-02-24
Publication date: 2010-04-14
Anticipated expiration: 2026-02-24
Also published as: JP2007232224A

Description

本発明は、ヒートポンプ回路の室外熱交換器と室内熱交換器の間に接続されて冷媒が双方向に流され、下流側の冷媒圧力を一定にすることが可能な双方向定圧膨張弁に関する。 The present invention relates to a bidirectional constant pressure expansion valve that is connected between an outdoor heat exchanger and an indoor heat exchanger of a heat pump circuit, allows refrigerant to flow in both directions, and makes the refrigerant pressure on the downstream side constant.

図１０に示した従来の双方向定圧膨張弁は、冷媒が流される流路１の軸方向に１対のボール弁機構２，２を有すると共に、それらボール弁機構２，２の間に可動体３を直動可能に備えている。また、可動体３は、その直動方向に延びたベローズ４と、そのベローズ４の挫屈を規制しかつベローズ４を伸縮可能に支持した直動支持機構５とを備えている。具体的には、直動支持機構５は、ベローズ４の両端に固定された可動盤５Ａ，５Ａから支持突部５Ｂ，５Ｂを互いに接近するように延ばし、それら支持突部５Ｂ，５Ｂに支持ピン５Ｃを貫通させて、支持突部５Ｂ，５Ｂの相対的な傾きを規制しつつ支持突部５Ｂ，５Ｂ同士が相互に直動可能な構造になっている。 The conventional bidirectional constant pressure expansion valve shown in FIG. 10 has a pair of ball valve mechanisms 2 and 2 in the axial direction of the flow path 1 through which the refrigerant flows, and a movable body between the ball valve mechanisms 2 and 2. 3 is provided so that it can move linearly. The movable body 3 includes a bellows 4 extending in the linear motion direction, and a linear motion support mechanism 5 that restricts the buckling of the bellows 4 and supports the bellows 4 so that the bellows 4 can extend and contract. Specifically, the linear motion support mechanism 5 extends the support protrusions 5B and 5B from the movable plates 5A and 5A fixed to both ends of the bellows 4 so as to approach each other, and a support pin is attached to the support protrusions 5B and 5B. The support protrusions 5B and 5B are configured to be able to move directly with respect to each other while passing through 5C and restricting the relative inclination of the support protrusions 5B and 5B.

可動体３の両端部からは各ボール弁機構２，２に向かって１対の押圧シャフト６，６が延びており、各押圧シャフト６，６がベローズ４の伸縮度に応じた押圧力で各ボール弁機構２，２のボール２Ａ，２Ａを押圧して、各ボール弁機構２の弁開度を調節する。即ち、冷媒が例えば図１０における左から右に向かって流れると、可動体３が下流側に移動して流路１内の壁部に当接し、一方の押圧シャフト６が下流側（同図の右側）のボール弁機構２を開弁状態に保持する。この結果、ベローズ４にボール弁機構２の下流側の冷媒圧力がかかり、他方の押圧シャフト６がベローズ４の弾発力に応じた押圧力で上流側（同図の左側）のボール弁機構２のボール２Ａを押圧する。これにより、上流側のボール弁機構２が下流側の冷媒圧力に応じた弁開度になり、下流側の冷媒を一定圧力にすることができる（例えば、特許文献１参照）。
特許第３４１８２７１号公報（段落［００２４］〜［００２８］、第１図） A pair of pressing shafts 6, 6 extend from both ends of the movable body 3 toward the ball valve mechanisms 2, 2, and each pressing shaft 6, 6 has a pressing force corresponding to the degree of expansion / contraction of the bellows 4. The balls 2A and 2A of the ball valve mechanisms 2 and 2 are pressed to adjust the valve opening of each ball valve mechanism 2. That is, for example, when the refrigerant flows from left to right in FIG. 10, the movable body 3 moves to the downstream side and comes into contact with the wall portion in the flow path 1, and one of the pressing shafts 6 is on the downstream side (in FIG. The ball valve mechanism 2 on the right side is held open. As a result, the refrigerant pressure on the downstream side of the ball valve mechanism 2 is applied to the bellows 4, and the other pressing shaft 6 is pressed upstream of the ball valve mechanism 2 on the upstream side (the left side in the figure) with a pressing force corresponding to the elastic force of the bellows 4. The ball 2A is pressed. Thereby, the ball valve mechanism 2 on the upstream side has a valve opening degree corresponding to the refrigerant pressure on the downstream side, and the downstream refrigerant can be kept at a constant pressure (see, for example, Patent Document 1).
Japanese Patent No. 3418271 (paragraphs [0024] to [0028], FIG. 1)

ところで、上記した従来の双方向定圧膨張弁では、可動体３の側面と流路１の内周面との間のクリアランスの範囲で、可動体３が直動方向と直交する方向にずれると、連結ピン５Ｃと支持突部５Ｂ，５Ｂとの間にモーメント負荷がかかり、それら連結ピン５Ｃと支持突部５Ｂ，５Ｂとの間の摺動抵抗がばらつく。すると、これに伴って冷媒圧力に対するベローズ４の伸縮量もばらつく。このため、従来の双方向定圧膨張弁では、冷媒を正確に一定圧力にすることが困難であった。 By the way, in the above-described conventional bidirectional constant pressure expansion valve, when the movable body 3 is displaced in the direction orthogonal to the linear motion direction within the clearance range between the side surface of the movable body 3 and the inner peripheral surface of the flow path 1, A moment load is applied between the connection pin 5C and the support protrusions 5B and 5B, and the sliding resistance between the connection pin 5C and the support protrusions 5B and 5B varies. As a result, the amount of expansion and contraction of the bellows 4 with respect to the refrigerant pressure also varies. For this reason, with the conventional bidirectional constant pressure expansion valve, it has been difficult to accurately set the refrigerant at a constant pressure.

本発明は、上記事情に鑑みてなされたもので、従来より正確に冷媒を一定圧力にすることが可能な双方向定圧膨張弁の提供を目的とする。 The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a bidirectional constant pressure expansion valve that can make a refrigerant at a constant pressure more accurately than before.

上記目的を達成するためになされた請求項１の発明に係る双方向定圧膨張弁（１０，３０）は、ヒートポンプ回路（９０）の室内熱交換器（９２Ａ）と室外熱交換器（９１Ａ）との間に接続されて冷媒が双方向に流され、下流側の冷媒圧力を一定にすることが可能な双方向定圧膨張弁（１０，３０）において、冷媒の流路（１１）を内部に有したボディ（１０Ｂ）と、ボディ（１０Ｂ）に設けられて、流路（１１）を一端側領域（Ｒ１）と中間領域（Ｒ３）と他端側領域（Ｒ２）とに区画する１対の対向壁（１３，１３Ｆ）と、１対の対向壁（１３，１３Ｆ）に貫通形成されて、略同軸上に配置された１対の弁口（１６Ａ，１６Ｂ）と、ボディ（１０Ｂ）に固定されて、一端側領域（Ｒ１）内で一方の弁口（１６Ａ）に対向配置され、一端側領域（Ｒ１）内の冷媒圧力が上昇するに従って一方の弁口（１６Ａ）から離れるように弾性変形する一端側感圧部（２０Ａ）と、ボディ（１０Ｂ）に固定されて、他端側領域（Ｒ２）内で他方の弁口（１６Ｂ）に対向配置され、他端側領域（Ｒ２）内の冷媒圧力が上昇するに従って他方の弁口（１６Ｂ）から離れるように弾性変形する他端側感圧部（２０Ｂ）と、中間領域（Ｒ３）に収容されて、１対の弁口（１６Ａ，１６Ｂ）の間を移動し、接近した側の弁口（１６Ａ，１６Ｂ）の弁開度を変更可能な可動弁体（１７，３３）と、１対の弁口（１６Ａ，１６Ｂ）にそれぞれ遊嵌され、可動弁体（１７，３３）の位置に応じて、一端側又は他端側の感圧部（２０Ａ，２０Ｂ）の何れか一方と可動弁体（１７，３３）との間で突っ張り状態になる１対の当接シャフト（１７Ｄ，３４）とを備えたところに特徴を有する。 In order to achieve the above object, the bidirectional constant pressure expansion valve (10, 30) according to the invention of claim 1 includes an indoor heat exchanger (92A) and an outdoor heat exchanger (91A) of the heat pump circuit (90). In the bidirectional constant pressure expansion valve (10, 30), which is connected between the two and is allowed to flow the refrigerant in both directions, and the refrigerant pressure on the downstream side can be kept constant, the refrigerant flow path (11) is provided inside. The body (10B) and a pair of opposing surfaces that are provided in the body (10B) and divide the flow path (11) into one end region (R1), an intermediate region (R3), and the other end region (R2). A wall (13, 13F) and a pair of opposed walls (13, 13F) are formed so as to penetrate the pair of valve ports (16A, 16B) disposed substantially coaxially, and fixed to the body (10B). In the one end side region (R1) and opposed to one valve port (16A) One end side pressure sensing part (20A) elastically deforming away from one valve port (16A) as the refrigerant pressure in the area (R1) rises, and the other end side area ( R2) is opposed to the other valve port (16B), and elastically deforms away from the other valve port (16B) as the refrigerant pressure in the other end region (R2) rises. It is accommodated in the part (20B) and the intermediate region (R3), moves between a pair of valve ports (16A, 16B), and can change the valve opening degree of the close valve port (16A, 16B) The movable valve body (17, 33) and the pair of valve ports (16A, 16B) are respectively loosely fitted, and depending on the position of the movable valve body (17, 33), the pressure sensitivity on one end side or the other end side Between one of the parts (20A, 20B) and the movable valve body (17, 33). Characterized in place and a pair of abutment shaft (17D, 34).

請求項２の発明は、請求項１に記載の双方向定圧膨張弁（１０，３０）において、一端側及び他端側の感圧部（２０Ａ，２０Ｂ）は、共に一端開放の感圧筒体（２１，５５）の開口端にダイヤフラム（２２）を張ってなり、感圧筒体（２１，５５）がボディ（１０Ｂ）に固定され、ダイヤフラム（２２）が弁口（１６Ａ，１６Ｂ）に対向配置されたところに特徴を有する。 According to a second aspect of the present invention, in the bidirectional constant pressure expansion valve (10, 30) according to the first aspect, the pressure-sensitive portions (20A, 20B) on one end side and the other end side are both open at one end. A diaphragm (22) is stretched at the open end of (21, 55), the pressure sensitive cylinder (21, 55) is fixed to the body (10B), and the diaphragm (22) faces the valve port (16A, 16B). It has a characteristic where it is placed.

請求項３の発明は、請求項２に記載の双方向定圧膨張弁（１０，３０）において、感圧筒体（２１，５５）の開口縁との間にダイヤフラム（２２）の外縁部を挟んで溶接されたダイヤフラム固定盤（５０）と、ダイヤフラム固定盤（５０）に貫通形成されて、冷媒を通過可能とした冷媒通過孔（５１）と、ダイヤフラム固定盤（５０）に貫通形成されて、当接シャフト（１７Ｄ，３４）が挿通したシャフト挿通孔（５２）と、シャフト挿通孔（５２）の開口縁に備えられ、通常はダイヤフラム（２２）に隙間を介して対向して、ダイヤフラム（２２）が所定量以上変形することを防止する過度変形防止部（５３）とを備えたところに特徴を有する。 According to a third aspect of the present invention, in the bidirectional constant pressure expansion valve (10, 30) according to the second aspect, the outer edge of the diaphragm (22) is sandwiched between the opening edge of the pressure-sensitive cylinder (21, 55). And a diaphragm fixing plate (50) welded in, a through hole formed in the diaphragm fixing plate (50) to allow a refrigerant to pass through, and a through hole formed in the diaphragm fixing plate (50). A shaft insertion hole (52) through which the contact shaft (17D, 34) is inserted, and an opening edge of the shaft insertion hole (52), are usually opposed to the diaphragm (22) through a gap, and the diaphragm (22 ) Is provided with an excessive deformation preventing portion (53) that prevents the deformation of a predetermined amount or more.

請求項４の発明は、請求項３に記載の双方向定圧膨張弁（１０）において、感圧筒体（５５）とダイヤフラム（２２）とダイヤフラム固定盤（５０）とを一体化した感圧ユニット（５７）と、対向壁（１３）から突出し、感圧ユニット（５７）を内側に圧入して任意の位置に保持可能な圧入筒部（５６）とを備えたところに特徴を有する。 According to a fourth aspect of the present invention, in the bidirectional constant pressure expansion valve (10) of the third aspect, the pressure sensitive unit (55), the diaphragm (22), and the diaphragm fixing plate (50) are integrated. (57) and a press-fit cylinder portion (56) that protrudes from the opposing wall (13) and press-fits the pressure-sensitive unit (57) inward and can be held at an arbitrary position.

請求項５の発明は、請求項１乃至４の何れかに記載の双方向定圧膨張弁（１０，３０）において、一方の弁口（１６Ａ）と当接シャフト（１７Ｄ，３４）との隙間の開口面積を、他方の弁口（１６Ｂ）と当接シャフト（１７Ｄ，３４）との隙間の開口面積より広くしたところに特徴を有する。 According to a fifth aspect of the present invention, in the bidirectional constant pressure expansion valve (10, 30) according to any one of the first to fourth aspects, the gap between the one valve port (16A) and the contact shaft (17D, 34) is provided. It is characterized in that the opening area is wider than the opening area of the gap between the other valve port (16B) and the contact shaft (17D, 34).

請求項６の発明は、請求項１乃至５の何れかに記載の双方向定圧膨張弁（１０，３０）において、一端側又は他端側の感圧部（２０Ａ，２０Ｂ）のうち室内熱交換器（９２Ａ）側の感圧部（２０Ｂ）の弾性係数と、室外熱交換器（９１Ａ）側の感圧部（２０Ａ）の弾性係数とを異ならせたところに特徴を有する。 A sixth aspect of the present invention is the bidirectional constant pressure expansion valve (10, 30) according to any one of the first to fifth aspects, wherein the indoor heat exchange is performed in the pressure sensitive part (20A, 20B) on one end side or the other end side. The elastic coefficient of the pressure sensitive part (20B) on the side of the vessel (92A) is different from the elastic coefficient of the pressure sensitive part (20A) on the side of the outdoor heat exchanger (91A).

請求項７の発明は、請求項１乃至６の何れかに記載の双方向定圧膨張弁（１０）において、１対の当接シャフト（１７Ｄ）は、可動弁体（１７）の両端部から延設されたところに特徴を有する。 A seventh aspect of the present invention is the bidirectional constant pressure expansion valve (10) according to any one of the first to sixth aspects, wherein the pair of contact shafts (17D) extend from both ends of the movable valve body (17). It is characterized by where it is installed.

請求項８の発明は、請求項１乃至７の何れかに記載の双方向定圧膨張弁（３０）において、１対の当接シャフト（３４）を、他端側及び一端側の感圧部（２０Ａ，２０Ｂ）にそれぞれ固定し、可動弁体（３３）を球体（３３）で構成したところに特徴を有する。 An eighth aspect of the present invention is the bidirectional constant pressure expansion valve (30) according to any one of the first to seventh aspects, wherein the pair of contact shafts (34) are connected to the pressure-sensitive portions on the other end side and one end side ( 20A and 20B), and the movable valve element (33) is composed of a spherical body (33).

請求項１の双方向定圧膨張弁（１０，３０）を、ヒートポンプ回路（９０）の室外熱交換器（９１Ａ）と室内熱交換器（９２Ａ）の間に接続し、ヒートポンプ回路（９０）を冷房運転と暖房運転との何れか一方にすると、双方向定圧膨張弁（１０，３０）には、一端側領域（Ｒ１）、一方の弁口（１６Ａ）、中間領域（Ｒ３）、他方の弁口（１６Ｂ）、他端側領域（Ｒ２）の順番に冷媒が流れる。すると、中間領域（Ｒ３）内の可動弁体（１７，３３）が冷媒に押されて下流側に移動し、下流側の弁口（１６Ｂ）に遊嵌された当接シャフト（１７Ｄ，３４）が、可動弁体（１７，３３）と他端側感圧部（２０Ｂ）との間で突っ張り状態になる。これにより、可動弁体（１７，３３）が他端側感圧部（２０Ｂ）によって位置決めされる。 The bidirectional constant pressure expansion valve (10, 30) of claim 1 is connected between the outdoor heat exchanger (91A) and the indoor heat exchanger (92A) of the heat pump circuit (90), and the heat pump circuit (90) is cooled. When one of the operation and the heating operation is performed, the bidirectional constant pressure expansion valve (10, 30) includes one end side region (R1), one valve port (16A), an intermediate region (R3), and the other valve port. (16B), the refrigerant flows in the order of the other end side region (R2). Then, the movable valve body (17, 33) in the intermediate region (R3) is pushed by the refrigerant and moves downstream, and the contact shaft (17D, 34) loosely fitted in the downstream valve port (16B). However, it will be in a stretch state between a movable valve body (17, 33) and a pressure sensing part (20B) at the other end. Thereby, a movable valve body (17, 33) is positioned by the other end side pressure sensing part (20B).

ここで、他端側領域（Ｒ２）内の冷媒圧力が比較的大きくなると、他端側感圧部（２０Ｂ）が弁口（１６Ｂ）から離れるように変形し、これに伴って可動弁体（１７，３３）が弁口（１６Ｂ）に接近して弁開度が小さくなり、他端側領域（Ｒ２）内の冷媒圧力が下がる。これとは逆に、他端側領域（Ｒ２）内の冷媒圧力が比較的小さくなると、他端側感圧部（２０Ｂ）が弁口（１６Ｂ）に近づくように変形し、これに伴って可動弁体（１７，３３）が弁口（１６Ｂ）から離れて弁開度が大きくなり、他端側領域（Ｒ２）内の冷媒圧力が上がる。これらにより、双方向定圧膨張弁（１０，３０）における下流側の冷媒圧力が一定になる。 Here, when the refrigerant pressure in the other end side region (R2) becomes relatively large, the other end side pressure sensing portion (20B) is deformed away from the valve port (16B), and accordingly, the movable valve body ( 17, 33) approaches the valve port (16B), the valve opening decreases, and the refrigerant pressure in the other end side region (R2) decreases. On the contrary, when the refrigerant pressure in the other end side region (R2) becomes relatively small, the other end side pressure sensing portion (20B) is deformed so as to approach the valve port (16B), and is moved accordingly. The valve body (17, 33) is separated from the valve port (16B), the valve opening is increased, and the refrigerant pressure in the other end region (R2) is increased. As a result, the downstream refrigerant pressure in the bidirectional constant pressure expansion valve (10, 30) becomes constant.

冷房運転と暖房運転とを切り替え、上記の場合とは冷媒が流れる方向が逆転して、一端側領域（Ｒ１）が下流側に位置した場合も同様に、一端側領域（Ｒ１）内の冷媒圧力が比較的大きくなると一方の弁口（１６Ａ）の弁開度が小さくなって下流側の冷媒圧力が上昇する一方、一端側領域（Ｒ１）内の冷媒圧力が比較的小さくなるとその弁口（１６Ａ）の弁開度が大きくなって、下流側の冷媒圧力が低下し、下流側の冷媒圧力が一定になる。なお、冷媒の流れる向きに拘わらず、可動弁体（１７，３３）が下流側に移動することで、可動弁体（１７，３３）と上流側の弁口（１６Ａ，１６Ｂ）との間は十分に離れ、上流側の弁口（１６Ａ，１６Ｂ）は常に開弁状態になる。 Similarly, when the cooling operation and the heating operation are switched and the direction in which the refrigerant flows is reversed from that in the above case and the one end side region (R1) is located on the downstream side, the refrigerant pressure in the one end side region (R1) is the same. Is relatively large, the valve opening degree of one of the valve openings (16A) is reduced and the refrigerant pressure on the downstream side rises. On the other hand, when the refrigerant pressure in the one end region (R1) is relatively small, the valve opening (16A) ), The downstream refrigerant pressure decreases, and the downstream refrigerant pressure becomes constant. Regardless of the direction in which the refrigerant flows, the movable valve element (17, 33) moves downstream so that the gap between the movable valve element (17, 33) and the upstream valve opening (16A, 16B) The valve ports (16A, 16B) on the upstream side are always opened and always open.

このように、本発明の双方向定圧膨張弁（１０，３０）によれば、下流側の冷媒圧力を一定にすることができる。しかも、一端側及び他端側の感圧部（２０Ａ，２０Ｂ）がボディ（１０Ｂ）に固定されているので、一端側及び他端側の感圧部（２０Ａ，２０Ｂ）自体が冷媒の流れる方向に応じて移動することはない。従って、従来のようにベローズの挫屈を規制しかつベローズを伸縮可能に支持する直動支持機構が不要になる。これにより、直動支持機構の摺動抵抗の影響がなくなり、従来より正確に冷媒を一定圧力にすることが可能になる。 Thus, according to the bidirectional constant pressure expansion valve (10, 30) of the present invention, the downstream refrigerant pressure can be made constant. Moreover, since the pressure sensitive parts (20A, 20B) on one end side and the other end side are fixed to the body (10B), the pressure sensitive parts (20A, 20B) themselves on the one end side and the other end side flow in the refrigerant. Will not move in response to. Therefore, a linear motion support mechanism that restricts the buckling of the bellows and supports the bellows so as to be extendable / contracted as in the prior art becomes unnecessary. Thereby, the influence of the sliding resistance of the linear motion support mechanism is eliminated, and the refrigerant can be kept at a constant pressure more accurately than in the past.

本発明の双方向定圧膨張弁（１０，３０）における一端側感圧部（２０Ａ）及び他端側感圧部（２０Ｂ）は、ダイヤフラム（２２）又はベローズの何れかを備えることで、冷媒圧力に応じて変形する構成にすることができる。また、ダイヤフラム（２２）を備えた構成にする場合には、例えば、請求項２の発明のように、一端開放の感圧筒体（２１）の開口にダイヤフラム（２２）を張り、感圧筒体（２１）をボディ（１０Ｂ）に固定すればよい。 The one end side pressure sensing part (20A) and the other end side pressure sensing part (20B) in the bidirectional constant pressure expansion valve (10, 30) of the present invention include either the diaphragm (22) or the bellows, so that the refrigerant pressure It can be configured to be deformed according to the above. Further, in the case of the configuration including the diaphragm (22), for example, as in the invention of claim 2, the diaphragm (22) is stretched over the opening of the pressure-sensitive cylinder (21) that is open at one end, and the pressure-sensitive cylinder. What is necessary is just to fix a body (21) to a body (10B).

請求項３の双方向定圧膨張弁（１０，３０）によれば、感圧筒体（２１，５５）の開口縁とダイヤフラム固定盤（５０）との間にダイヤフラム（２２）の外縁部を挟んで溶接することで、感圧筒体（２１，５５）へのダイヤフラム（２２）の固定が安定する。また、ダイヤフラム固定盤（５０）に備えた過度変形防止部（５３）を、所定量変形したダイヤフラム（２２）に直接又は間接的に当接させることで、ダイヤフラム（２２）の過度の変形を防止することができる。 According to the bidirectional constant pressure expansion valve (10, 30) of claim 3, the outer edge portion of the diaphragm (22) is sandwiched between the opening edge of the pressure sensitive cylinder (21, 55) and the diaphragm fixing plate (50). The diaphragm (22) is stably fixed to the pressure-sensitive cylinder (21, 55). Moreover, the excessive deformation | transformation prevention part (53) with which the diaphragm fixing plate (50) was equipped is made to contact the diaphragm (22) which deform | transformed predetermined amount directly or indirectly, and an excessive deformation | transformation of a diaphragm (22) is prevented. can do.

請求項４の双方向定圧膨張弁（１０）によれば、感圧ユニット（５７）の圧入筒部（５６）に対する圧入位置を適宜調節することにより、双方向定圧膨張弁（１０）の各構成部品の寸法のばらつきによる影響を抑えて、双方向定圧膨張弁（１０）の品質を均一にすることができる。 According to the bidirectional constant pressure expansion valve (10) of claim 4, each configuration of the bidirectional constant pressure expansion valve (10) is adjusted by appropriately adjusting the press-fitting position of the pressure-sensitive unit (57) with respect to the press-fitting cylinder portion (56). The quality of the bidirectional constant pressure expansion valve (10) can be made uniform by suppressing the influence due to the dimensional variation of the parts.

また、本発明の双方向定圧膨張弁（１０，３０）は、従来の双方向定圧膨張弁と異なり、感圧部（２０Ａ，２０Ｂ）を一端側と他端側とに対にして設けたので、室内熱交換器（９２Ａ）側の弁口（１６Ｂ）の冷媒圧力に対する弁開度の特性と、室外熱交換器（９１Ａ）側の弁口（１６Ａ）の冷媒圧力に対する弁開度の特性とを、それぞれ別々に適した特性に設定することができる。 In addition, unlike the conventional bidirectional constant pressure expansion valve, the bidirectional constant pressure expansion valve (10, 30) of the present invention is provided with the pressure sensitive parts (20A, 20B) in pairs on one end side and the other end side. The characteristics of the valve opening with respect to the refrigerant pressure of the valve opening (16B) on the indoor heat exchanger (92A) side, and the characteristics of the valve opening with respect to the refrigerant pressure of the valve opening (16A) on the outdoor heat exchanger (91A) side Can be set to characteristics suitable for each.

具体的には、請求項５の双方向定圧膨張弁（１０，３０）のように、暖房冷房いずれかの運転時に下流側に位置する一方の弁口（１６Ａ）と当接シャフト（１７Ｄ，３４）との隙間の開口面積を、他方の弁口（１６Ｂ）と当接シャフト（１７Ｄ，３４）との隙間の開口面積より広くしてもよい。これにより、暖房冷房の何れか一方の運転時に双方向定圧膨張弁（１０，３０）にて制御されて流される冷媒流量が、他方の運転時に制御されて流される冷媒流量より大きくなり、比較的に大流量（大容量）を必要とする暖房運転時になどに適切に対応することができる。 Specifically, as in the bi-directional constant pressure expansion valve (10, 30) of claim 5, one of the valve ports (16A) and the contact shaft (17D, 34) located on the downstream side during either heating or cooling operation. ) May be wider than the opening area of the gap between the other valve port (16B) and the contact shaft (17D, 34). As a result, the refrigerant flow rate controlled and flowed by the bidirectional constant pressure expansion valve (10, 30) during one of the heating and cooling operations is larger than the refrigerant flow rate controlled and flowed during the other operation, It is possible to appropriately cope with the heating operation that requires a large flow rate (large capacity).

さらに、請求項６の双方向定圧膨張弁（１０，３０）のように、一端側又は他端側の感圧部（２０Ａ，２０Ｂ）のうち冷房運転時に下流側に位置する室内熱交換器（９２Ａ）側の感圧部（２０Ｂ）の弾性係数と、暖房運転時に下流側に位置する室外熱交換器（９１Ａ）側の感圧部（２０Ａ）の弾性係数とを異ならせて、冷媒圧力及び冷媒流量が異なる冷房運転時と暖房運転時のそれぞれにおいて冷媒の圧力と流量を制御可能な最適な弁のリフト特性を得ることができる。 Further, as in the bi-directional constant pressure expansion valve (10, 30) of claim 6, the indoor heat exchanger (10A, 20B) located on the downstream side during the cooling operation of the pressure sensing part (20A, 20B) on one end side or the other end side. The elastic coefficient of the pressure-sensitive part (20B) on the 92A) side and the elastic coefficient of the pressure-sensitive part (20A) on the outdoor heat exchanger (91A) side located on the downstream side during the heating operation are made different from each other. It is possible to obtain an optimal valve lift characteristic capable of controlling the pressure and flow rate of the refrigerant during cooling operation and heating operation with different refrigerant flow rates.

請求項７の構成によれば、１対の当接シャフト（１７Ｄ）が、可動弁体（１７）の両端部から延設されているので、一端側及び他端側の感圧部（２０Ａ，２０Ｂ）の構造を簡素化することができる。 According to the structure of Claim 7, since a pair of contact shaft (17D) is extended from the both ends of the movable valve body (17), the pressure-sensitive part (20A, 20B) can be simplified.

なお、請求項８の構成のように、１対の当接シャフト（３４）を、他端側及び一端側の感圧部（２０Ａ，２０Ｂ）にそれぞれ固定し、可動弁体（３３）を球体（３３）で構成してもよい。 As in the configuration of the eighth aspect, the pair of contact shafts (34) are fixed to the pressure-sensitive portions (20A, 20B) on the other end side and the one end side, respectively, and the movable valve body (33) is a spherical body. (33) may be used.

［第１実施形態］
以下、本発明の一実施形態を図１〜図５に基づいて説明する。
図１に示された本実施形態の双方向定圧膨張弁１０のボディ１０Ｂは、パイプ部材１２の内部に１対の対向壁１３，１３を備えてなる。パイプ部材１２は、例えば、断面円形をなして真っ直ぐ延びており、両端寄り位置でテーパー状に縮径され、中間部分より両端部の径が小さくなっている。 [First Embodiment]
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
A body 10 B of the bidirectional constant pressure expansion valve 10 of the present embodiment shown in FIG. 1 includes a pair of opposing walls 13 and 13 inside a pipe member 12. For example, the pipe member 12 has a circular cross section and extends straight, and is reduced in a tapered shape at positions near both ends, with the diameters at both ends being smaller than the intermediate portion.

１対の対向壁１３，１３は、パイプ部材１２と別部品になっており、これら両対向壁１３，１３の間には、円筒状のガイド筒体１５Ａが備えられている。そして、各対向壁１３の中心に円形凹所１５Ｂが形成され、各対向壁１３の円形凹所１５Ｂにガイド筒体１５Ａの各端部が嵌合されている。これにより、対向壁１３，１３同士が互いに心だしされている。また、円形凹所１５Ｂの奥面にガイド筒体１５Ａの先端が突き当てられて対向壁１３，１３同士が位置決めされ、対向壁１３，１３同士の間隔が一定の大きさになっている。 The pair of opposed walls 13 and 13 are separate parts from the pipe member 12, and a cylindrical guide cylinder 15 A is provided between the opposed walls 13 and 13. A circular recess 15B is formed at the center of each opposing wall 13, and each end of the guide cylinder 15A is fitted in the circular recess 15B of each opposing wall 13. Thereby, the opposing walls 13 and 13 are centered on each other. Moreover, the front end of the guide cylinder 15A is abutted against the inner surface of the circular recess 15B to position the opposing walls 13 and 13, and the interval between the opposing walls 13 and 13 is constant.

各対向壁１３の外周面には係止溝１４が全周に亘って形成されている。これに対応して、パイプ部材１２の中間部分における軸方向の２箇所には、パイプ部材１２の一部を周方向全体に亘って内側に屈曲させて１対の突条１２Ｔ，１２Ｔが形成されている。そして、各対向壁１３，１３の係止溝１４内に各突条１２Ｔを係合させて、対向壁１３，１３がパイプ部材１２内に位置決め固定されると共に、対向壁１３，１３の外周面とパイプ部材１２の内周面との隙間が塞がれている。これにより、パイプ部材１２内の流路１１が１対の対向壁１３，１３によって一端側の一端側領域Ｒ１と他端側の他端側領域Ｒ２とそれら一端側領域Ｒ１と他端側領域Ｒ２の中間の中間領域Ｒ３とに区画されている。 Locking grooves 14 are formed on the outer peripheral surface of each facing wall 13 over the entire circumference. Correspondingly, a pair of protrusions 12T and 12T are formed by bending a part of the pipe member 12 inward in the entire circumferential direction at two axial positions in the intermediate portion of the pipe member 12. ing. And each protrusion 12T is engaged in the locking groove 14 of each opposing wall 13 and 13, and the opposing walls 13 and 13 are positioned and fixed in the pipe member 12, and the outer peripheral surface of the opposing walls 13 and 13 And the inner peripheral surface of the pipe member 12 are closed. Thereby, the flow path 11 in the pipe member 12 is connected to the one end side region R1 on the one end side, the other end side region R2 on the other end side, the one end side region R1, and the other end side region R2 by the pair of opposing walls 13 and 13. And an intermediate region R3 in the middle.

対向壁１３，１３の中心部には、弁口１６Ａ，１６Ｂが形成されている。これら弁口１６Ａ，１６Ｂは、開口形状が共に円形になっており、互いに同軸上に配置されている。また、前記したガイド筒体１５Ａ及び円形凹所１５Ｂはこれら弁口１６Ａ，１６Ｂの同心円上に配置されている。さらに、一方の対向壁１３の弁口１６Ａ（図１の上側の弁口１６Ａ）の内径は、他方の対向壁１３の弁口１６Ｂの内径より大きくなっている。そして、これら弁口１６Ａ，１６Ｂを通して冷媒が一端側領域Ｒ１と中間領域Ｒ３との間、中間領域Ｒ３と他端側領域Ｒ２との間を流れる。また、両弁口１６Ａ，１６Ｂにおける中間領域Ｒ３側の開口縁には、テーパー状の弁座１６Ｚが形成されている。 Valve ports 16 A and 16 B are formed at the center of the opposing walls 13 and 13. These valve ports 16A and 16B have both circular openings, and are arranged coaxially with each other. Further, the guide cylinder 15A and the circular recess 15B described above are arranged on concentric circles of the valve ports 16A and 16B. Further, the inner diameter of the valve port 16A of the one opposing wall 13 (the upper valve port 16A in FIG. 1) is larger than the inner diameter of the valve port 16B of the other opposing wall 13. The refrigerant flows through the valve ports 16A and 16B between the one end side region R1 and the intermediate region R3 and between the intermediate region R3 and the other end side region R2. A tapered valve seat 16Z is formed at the opening edge on the intermediate region R3 side in both valve ports 16A and 16B.

ガイド筒体１５Ａの両端部には、ガイド筒体１５Ａを軸方向と直交する方向に貫通した冷媒通過孔１５Ｃがそれぞれ形成され、これら冷媒通過孔１５Ｃを通して冷媒がガイド筒体１５Ａの内側と外側との間を流れる。また、各対向壁１３，１３には、ガイド筒体１５Ａの両端部を囲むようにテーパー面１５Ｔ，１５Ｔが形成されている。そして、例えば、一端側の冷媒通過孔１５Ｃからガイド筒体１５Ａの外側に向かって流れた冷媒を一端側のテーパー面１５Ｔによってガイド筒体１５Ａの軸方向に案内すると共に、ガイド筒体１５Ａの外面に沿って流れた冷媒を他端側のテーパー面１５Ｔによって他端側の冷媒通過孔１５Ｃ内に案内する役割を果たす。 Refrigerant passage holes 15C penetrating the guide cylinder 15A in a direction orthogonal to the axial direction are formed at both ends of the guide cylinder 15A, respectively, and the refrigerant passes through the refrigerant passage holes 15C to the inside and outside of the guide cylinder 15A. Flowing between. Further, tapered surfaces 15T and 15T are formed on the opposing walls 13 and 13 so as to surround both end portions of the guide cylinder 15A. For example, the refrigerant flowing from the refrigerant passage hole 15C on the one end side toward the outside of the guide cylinder 15A is guided in the axial direction of the guide cylinder 15A by the tapered surface 15T on the one end side, and the outer surface of the guide cylinder 15A. It plays a role of guiding the refrigerant flowing along the other end side into the refrigerant passage hole 15C on the other end side by the tapered surface 15T on the other end side.

ガイド筒体１５Ａの内部には、可動弁体１７が収容されている。可動弁体１７は、ガイド筒体１５Ａと同軸方向に延びた円柱体構造をなし、両端部に向かうに従って先細りになっている。具体的には、可動弁体１７は、軸方向の中央部に摺動部１７Ａを備え、その摺動部１７Ａの両端から両先端に向かって、それぞれ遊嵌部１７Ｂと弁部１７Ｃと当接シャフト１７Ｄとを順番に備えている。 A movable valve body 17 is accommodated in the guide cylinder 15A. The movable valve body 17 has a cylindrical structure extending in the same direction as the guide cylinder 15A, and tapers toward both ends. Specifically, the movable valve body 17 includes a sliding portion 17A at the axial center, and abuts the loose fitting portion 17B and the valve portion 17C from both ends of the sliding portion 17A toward both ends. A shaft 17D is provided in order.

摺動部１７Ａは、ガイド筒体１５Ａの内面を摺動可能な大きさをなし、これにより、可動弁体１７がガイド筒体１５Ａ及び弁口１６Ａ，１６Ｂに心だしされている。 The sliding portion 17A has a size capable of sliding on the inner surface of the guide cylinder 15A, whereby the movable valve body 17 is centered on the guide cylinder 15A and the valve ports 16A and 16B.

各当接シャフト１７Ｄ，１７Ｄは各弁口１６Ａ，１６Ｂに遊嵌されている。そして、各弁口１６Ａ，１６Ｂの内周面と当接シャフト１７Ｄ，１７Ｄの外周面との間の隙間を通して冷媒が弁口１６Ａ，１６Ｂを流れる。また、両当接シャフト１７Ｄ，１７Ｄは同じ外径になっている。そして、前述したように、一方の弁口１６Ａの内径が、他方の弁口１６Ｂの内径より大きいので、一方の弁口１６Ａと当接シャフト１７Ｄとの隙間の開口面積が、他方の弁口１６Ｂと当接シャフト１７Ｄとの隙間の開口面積より広くなっている。 Each contact shaft 17D, 17D is loosely fitted to each valve port 16A, 16B. And a refrigerant | coolant flows through valve opening 16A, 16B through the clearance gap between the internal peripheral surface of each valve opening 16A, 16B, and the outer peripheral surface of contact shaft 17D, 17D. Moreover, both contact shafts 17D and 17D have the same outer diameter. As described above, since the inner diameter of one valve port 16A is larger than the inner diameter of the other valve port 16B, the opening area of the gap between one valve port 16A and the contact shaft 17D is the other valve port 16B. And the opening area of the gap between the contact shaft 17D and the contact shaft 17D.

両遊嵌部１７Ｂ，１７Ｂは、摺動部１７Ａに対して段付き状に径が小さくなっており、遊嵌部１７Ｂとガイド筒体１５Ａの内面との間に形成された隙間は、冷媒が通過することが可能な大きさになっている。 Both loose fitting portions 17B and 17B have a stepped diameter with respect to the sliding portion 17A, and the gap formed between the loose fitting portion 17B and the inner surface of the guide cylinder 15A is filled with refrigerant. It is large enough to pass.

弁部１７Ｃは、一端が遊嵌部１７Ｂと同じ外径をなし、他端が当接シャフト１７Ｄと同じ外径をなしたテーパー形状になっている。また、弁部１７Ｃのテーパーの傾斜は、例えば、弁口１６Ａ，１６Ｂの開口縁に備えたテーパー状の弁座１６Ｚの傾斜と同じ角度になっている。そして、図３に示すように可動弁体１７がガイド筒体１５Ａ内を一端側に移動すると、一方の弁部１７Ｃが一方の弁口１６Ａに接近してその弁口１６Ａの弁開度が調節可能となると共に、他方の弁部１７Ｃが他方の弁口１６Ｂから十分に離れて弁口１６Ｂが開弁状態になる。これとは逆に、図１に示すように可動弁体１７がガイド筒体１５Ａ内を他端側に移動すると、他方の弁部１７Ｃが一方の弁口１６Ｂに接近してその弁口１６Ｂの弁開度が調節可能となると共に、一方の弁部１７Ｃが他方の弁口１６Ａから十分に離れて弁口１６Ａが開弁状態になる。 The valve portion 17C has a tapered shape in which one end has the same outer diameter as the loose fitting portion 17B and the other end has the same outer diameter as the contact shaft 17D. Further, the inclination of the taper of the valve portion 17C is, for example, the same angle as the inclination of the tapered valve seat 16Z provided at the opening edges of the valve ports 16A and 16B. Then, as shown in FIG. 3, when the movable valve body 17 moves to the one end side within the guide cylinder 15A, one valve portion 17C approaches one valve port 16A and the valve opening degree of the valve port 16A is adjusted. At the same time, the other valve portion 17C is sufficiently separated from the other valve port 16B, and the valve port 16B is opened. On the contrary, when the movable valve body 17 moves to the other end side within the guide cylinder 15A as shown in FIG. 1, the other valve portion 17C approaches one valve port 16B, and the valve port 16B While the valve opening can be adjusted, the one valve portion 17C is sufficiently separated from the other valve port 16A, and the valve port 16A is opened.

各弁口１６Ａ，１６Ｂの弁開度を調節するために、ボディ１０Ｂの一部としての各対向壁１３，１３には、本発明に係る一端側感圧部２０Ａと他端側感圧部２０Ｂとが組み付けられている。 In order to adjust the valve opening degree of each valve port 16A, 16B, each opposing wall 13, 13 as a part of the body 10B is provided with one end side pressure sensing portion 20A and the other end side pressure sensing portion 20B according to the present invention. And are assembled.

一端側感圧部２０Ａ及び他端側感圧部２０Ｂは、共に一端開放の感圧筒体２１の開口にダイヤフラム２２を張ってなる。図４に示すように、感圧筒体２１の筒壁は、開口端側の外径が途中で段付き状に拡径され、その筒壁の開口端から側方にフランジ部２１Ｆが張り出されている。感圧筒体２１に対してダイヤフラム２２を挟んだ位置にはダイヤフラム固定盤５０が備えられている。ダイヤフラム固定盤５０は、一端有底の扁平円筒形状をなし、その開口端から側方にフランジ部５０Ｆが張り出している。このフランジ部５０Ｆは感圧筒体２１のフランジ部２１Ｆと同形状をなし、これらフランジ部２１Ｆ，５０Ｆの間にダイヤフラム２２の外縁部を挟み、両フランジ部２１Ｆ，５０Ｆ及びダイヤフラム２２が溶接されている。また、ダイヤフラム固定盤５０の底壁５０Ｂにおける中心部からは、ダイヤフラム２２に向けて過度変形防止部５３が膨出している。そして、過度変形防止部５３の先端面はダイヤフラム２２の中心部分と対向した状態になっている。これにより、ダイヤフラム２２がダイヤフラム固定盤５０側に所定量まで撓むと過度変形防止部５３に当接して、過度の変形が防がれる。 The one-end-side pressure-sensitive portion 20A and the other-end-side pressure-sensitive portion 20B are both formed by extending a diaphragm 22 over the opening of the pressure-sensitive cylinder 21 that is open at one end. As shown in FIG. 4, the cylinder wall of the pressure-sensitive cylinder 21 has an outer diameter on the opening end side that is enlarged in a stepped manner in the middle, and a flange portion 21F projects laterally from the opening end of the cylinder wall. Has been. A diaphragm fixing plate 50 is provided at a position sandwiching the diaphragm 22 with respect to the pressure sensitive cylinder 21. The diaphragm fixing plate 50 has a flat cylindrical shape with a bottom at one end, and a flange portion 50F projects from the opening end to the side. The flange portion 50F has the same shape as the flange portion 21F of the pressure-sensitive cylinder 21. The outer edge portion of the diaphragm 22 is sandwiched between the flange portions 21F and 50F, and both the flange portions 21F and 50F and the diaphragm 22 are welded. Yes. Further, the excessive deformation preventing portion 53 bulges toward the diaphragm 22 from the center portion of the bottom wall 50B of the diaphragm fixing platen 50. And the front end surface of the excessive deformation | transformation prevention part 53 is in the state facing the center part of the diaphragm 22. As shown in FIG. As a result, when the diaphragm 22 is bent to a predetermined amount toward the diaphragm fixing plate 50, the diaphragm 22 comes into contact with the excessive deformation preventing portion 53, and excessive deformation is prevented.

過度変形防止部５３の先端面における中心には、当接シャフト１７Ｄを挿通可能なシャフト挿通孔５２が貫通形成されている。また、底壁５０Ｂのうち過度変形防止部５３の周りには、複数の冷媒通過孔５１が貫通形成されている。 A shaft insertion hole 52 through which the contact shaft 17 D can be inserted is formed through the center of the distal end surface of the excessive deformation preventing portion 53. A plurality of refrigerant passage holes 51 are formed through the bottom wall 50B around the excessive deformation preventing portion 53.

感圧筒体２１の内部には、圧縮コイルバネ２４が収容され、ダイヤフラム２２の内面に宛がったインナー支持盤２３に圧縮コイルバネ２４の一端部が押し付けられている。インナー支持盤２３は、中心部がダイヤフラム２２に向かって突出しており、その突出部分の先端面のみがダイヤフラム２２に当接している。また、インナー支持盤２３の外縁部は感圧筒体２１における筒壁の段差部２１Ｄに隙間を介して対向している。そして、ダイヤフラム２２が感圧筒体２１の奥側に所定量まで撓んだ際に、インナー支持盤２３と段差部２１Ｄとが当接して、ダイヤフラム２２の過度変形を防止する。 A compression coil spring 24 is accommodated inside the pressure-sensitive cylinder 21, and one end of the compression coil spring 24 is pressed against the inner support plate 23 that is directed to the inner surface of the diaphragm 22. The center portion of the inner support plate 23 protrudes toward the diaphragm 22, and only the front end surface of the protruding portion is in contact with the diaphragm 22. Further, the outer edge portion of the inner support plate 23 is opposed to the step portion 21 D of the cylindrical wall in the pressure-sensitive cylindrical body 21 via a gap. And when the diaphragm 22 bends to the back side of the pressure-sensitive cylinder 21 to a predetermined amount, the inner support plate 23 and the stepped portion 21D come into contact with each other to prevent excessive deformation of the diaphragm 22.

なお、感圧筒体２１は、内部を真空や大気圧等の一定圧力に保つようになっている。また、円環状突部１８には、軸方向と直交する方向に貫通孔１８Ａが形成されており、この貫通孔１８Ａを通してダイヤフラム２２と対向壁１３との間の空間が一端側領域Ｒ１（又は、他端側領域Ｒ２）全体に連通している。 The pressure sensitive cylinder 21 is configured to keep the inside at a constant pressure such as vacuum or atmospheric pressure. Further, the annular protrusion 18 is formed with a through hole 18A in a direction orthogonal to the axial direction, and the space between the diaphragm 22 and the opposing wall 13 through the through hole 18A is one end side region R1 (or The other end side region R2) communicates with the whole.

上記した感圧筒体２１、ダイヤフラム２２、インナー支持盤２３、圧縮コイルバネ２４及びダイヤフラム固定盤５０の複数の部品は、上記した溶接により一体化されて感圧ユニット５７になっている。この感圧ユニット５７を各対向壁１３，１３に取り付けるために、各対向壁１３，１３のうち中間領域Ｒ３との反対面には、外寄り部分に円環状突部１８が形成され、その円環状突部１８の外縁部から係止片１９が起立している。そして、感圧ユニット５７におけるダイヤフラム固定盤５０の円筒壁５０Ａを円環状突部１８の内側に押し込んで芯だしすると共に、フランジ部２１Ｆ，５０Ｆの外縁部を円環状突部１８の端面に押し付けて軸方向を位置決めした状態で、係止片１９がフランジ部２１Ｆ，５０Ｆ側に押し倒されている。これにより、感圧ユニット５７，５７が各対向壁１３，１３に固定されて一端側感圧部２０Ａと他端側感圧部２０Ｂが構成されている。 A plurality of components such as the pressure-sensitive cylinder 21, the diaphragm 22, the inner support plate 23, the compression coil spring 24, and the diaphragm fixing plate 50 are integrated by the above-described welding to form a pressure-sensitive unit 57. In order to attach the pressure-sensitive unit 57 to each of the opposing walls 13 and 13, an annular protrusion 18 is formed on the outer surface of the opposing walls 13 and 13 opposite to the intermediate region R3. A locking piece 19 stands up from the outer edge of the annular protrusion 18. Then, the cylindrical wall 50A of the diaphragm fixing plate 50 in the pressure-sensitive unit 57 is pushed into the annular projecting portion 18 for centering, and the outer edge portions of the flange portions 21F and 50F are pressed against the end surface of the annular projecting portion 18. With the axial direction positioned, the locking piece 19 is pushed down toward the flange portions 21F and 50F. Thereby, the pressure-sensitive units 57 and 57 are fixed to the opposing walls 13 and 13 to constitute the one-end-side pressure-sensitive portion 20A and the other-end-side pressure-sensitive portion 20B.

上記したダイヤフラム２２及び圧縮コイルバネ２４を合わせた弾性係数は、一端側と他端側の感圧部２０Ａ，２０Ｂ（図１参照）の間で異なっている。具体的には、他端側感圧部２０Ｂの弾性係数が、一端側感圧部２０Ａの弾性係数より大きくなっている。また前述したように、一方の弁口１６Ａと当接シャフト１７Ｄとの隙間の開口面積が、他方の弁口１６Ｂと当接シャフト１７Ｄとの隙間の開口面積より広くなっており、これらの弾性係数と開口面積とを所定の値に設定して組み合わせることで、他端側領域Ｒ２が下流になった場合のその他端側領域Ｒ２の冷媒圧力が、一端側領域Ｒ１が下流になった場合のその一端側領域Ｒ１の冷媒圧力より大きくなるように構成されている。 The combined elastic coefficient of the diaphragm 22 and the compression coil spring 24 is different between the pressure-sensitive portions 20A and 20B (see FIG. 1) on one end side and the other end side. Specifically, the elastic coefficient of the other end side pressure sensitive part 20B is larger than the elastic coefficient of the one end side pressure sensitive part 20A. Further, as described above, the opening area of the gap between one valve port 16A and the contact shaft 17D is larger than the opening area of the gap between the other valve port 16B and the contact shaft 17D, and these elastic coefficients. And the opening area are set to a predetermined value and combined so that the refrigerant pressure in the other end region R2 when the other end region R2 is downstream is the same as that when the one end region R1 is downstream. It is comprised so that it may become larger than the refrigerant | coolant pressure of one end side area | region R1.

本実施形態に係る双方向定圧膨張弁１０の構成の説明は以上であり、次に、この双方向定圧膨張弁１０を、図５に示したヒートポンプ回路９０に組み付けた場合の動作について以下説明する。このヒートポンプ回路９０は、例えば、一般家庭用のルームエアコンに備えられている。ヒートポンプ回路９０には室外熱交換器９１Ａと室内熱交換器９２Ａとが備えられ、その室外熱交換器９１Ａは、ルームエアコンの室外機９１に組み込まれる一方、室内熱交換器９２Ａは室内機９２に組み込まれている。そして、１対の管路９６Ａ，９６Ｂによってこれら室外熱交換器９１Ａと室内熱交換器９２Ａとの間が接続されて、室外熱交換器９１Ａ及び室内熱交換器９２Ａを含む冷媒循環路９６が形成され、冷媒がこれら室外熱交換器９１Ａ及び室内熱交換器９２Ａを通過して冷媒循環路９６を循環する。そして、冷媒が室外熱交換器９１Ａを通過する際に冷媒と外気との間で熱交換が行われ、冷媒が室内熱交換器９２Ａを通過する際に冷媒と室内の空気との間で熱交換が行われる。 The configuration of the bidirectional constant pressure expansion valve 10 according to the present embodiment has been described above. Next, the operation when the bidirectional constant pressure expansion valve 10 is assembled to the heat pump circuit 90 shown in FIG. 5 will be described below. . The heat pump circuit 90 is provided in a room air conditioner for general households, for example. The heat pump circuit 90 includes an outdoor heat exchanger 91A and an indoor heat exchanger 92A. The outdoor heat exchanger 91A is incorporated in the outdoor unit 91 of the room air conditioner, while the indoor heat exchanger 92A is installed in the indoor unit 92. It has been incorporated. The outdoor heat exchanger 91A and the indoor heat exchanger 92A are connected by a pair of pipes 96A and 96B to form a refrigerant circulation path 96 including the outdoor heat exchanger 91A and the indoor heat exchanger 92A. Then, the refrigerant passes through the outdoor heat exchanger 91A and the indoor heat exchanger 92A and circulates in the refrigerant circulation path 96. Then, when the refrigerant passes through the outdoor heat exchanger 91A, heat exchange is performed between the refrigerant and the outside air, and when the refrigerant passes through the indoor heat exchanger 92A, heat exchange is performed between the refrigerant and the indoor air. Is done.

本実施形態の双方向定圧膨張弁１０は、室外機９１内に組み付けられると共に、室外熱交換器９１Ａと室内熱交換器９２Ａとの間を連絡する一方の管路９６Ａの途中に接続されている。そして、ボディ１０Ｂのうち図１の上側に示した一端側領域Ｒ１が室外熱交換器９１Ａに常時連通する一方、図１の下側に示した他端側領域Ｒ２が室内熱交換器９２Ａに常時連通した状態になっている。また、室外機９１側では、他方の管路９６Ｂの途中に四方弁９３を介して圧縮機９４が接続されている。そして、ヒートポンプ回路９０を冷房運転と暖房運転とに切り替えると、四方弁９３が作動して、冷媒循環路９６を流れる冷媒の向きが逆転する。 The bidirectional constant pressure expansion valve 10 of the present embodiment is assembled in the outdoor unit 91 and connected in the middle of one conduit 96A that communicates between the outdoor heat exchanger 91A and the indoor heat exchanger 92A. . And one end side area | region R1 shown to the upper side of FIG. 1 among body 10B is always connected to outdoor heat exchanger 91A, while the other end side area | region R2 shown to the lower side of FIG. 1 is always connected to indoor heat exchanger 92A. It is in a state of communication. On the outdoor unit 91 side, a compressor 94 is connected to the other pipe 96B through a four-way valve 93. When the heat pump circuit 90 is switched between the cooling operation and the heating operation, the four-way valve 93 is activated, and the direction of the refrigerant flowing through the refrigerant circulation path 96 is reversed.

さて、ヒートポンプ回路９０の冷房運転時には、一方の管路９６Ａにおいては、冷媒が室内熱交換器９２Ａから室外熱交換器９１Ａに流され、このとき、双方向定圧膨張弁１０においては、図１の矢印で示したように、冷媒が一端側領域Ｒ１、一方の弁口１６Ａ、中間領域Ｒ３、他方の弁口１６Ｂ、他端側領域Ｒ２の順番に流れる。すると、中間領域Ｒ３内の可動弁体１７が冷媒に押されて下流側（この場合は図１の下側）に移動し、下流側の弁口１６Ｂに遊嵌された当接シャフト１７Ｄが、可動弁体１７と他端側感圧部２０Ｂとの間で突っ張り状態になる。これにより、可動弁体１７が他端側感圧部２０Ｂによって位置決めされる。 Now, during the cooling operation of the heat pump circuit 90, in one pipe 96A, the refrigerant flows from the indoor heat exchanger 92A to the outdoor heat exchanger 91A. At this time, in the bidirectional constant pressure expansion valve 10, as shown in FIG. As indicated by the arrows, the refrigerant flows in the order of one end side region R1, one valve port 16A, intermediate region R3, the other valve port 16B, and the other end side region R2. Then, the movable valve element 17 in the intermediate region R3 is pushed by the refrigerant and moves downstream (in this case, the lower side in FIG. 1), and the contact shaft 17D loosely fitted in the downstream valve port 16B is The movable valve element 17 and the pressure sensor 20B on the other end side are stretched. Thereby, the movable valve body 17 is positioned by the other end side pressure sensing part 20B.

ここで、他端側領域Ｒ２内の冷媒圧力が比較的大きくなると、他端側感圧部２０Ｂのダイヤフラム２２が弁口１６Ｂから離れるように変形し、これに伴って可動弁体１７が弁口１６Ｂに接近して弁開度が小さくなり、他端側領域Ｒ２内の冷媒圧力が下がる。これとは逆に、他端側領域Ｒ２内の冷媒圧力が比較的小さくなると、他端側感圧部２０Ｂのダイヤフラム２２が弁口１６Ｂに近づくように変形し、これに伴って可動弁体１７が弁口１６Ｂから離れて弁開度が大きくなり、他端側領域Ｒ２内の冷媒圧力が上がる。これにより、下流側の冷媒圧力を一定にすることができる。 Here, when the refrigerant pressure in the other end side region R2 becomes relatively large, the diaphragm 22 of the other end side pressure sensing portion 20B is deformed so as to be separated from the valve port 16B, and accordingly, the movable valve body 17 is moved to the valve port. The valve opening degree decreases toward 16B, and the refrigerant pressure in the other end region R2 decreases. On the contrary, when the refrigerant pressure in the other end side region R2 becomes relatively small, the diaphragm 22 of the other end side pressure sensing portion 20B is deformed so as to approach the valve port 16B, and accordingly, the movable valve body 17 is deformed. Is away from the valve port 16B, the valve opening increases, and the refrigerant pressure in the other end region R2 increases. Thereby, the refrigerant pressure on the downstream side can be made constant.

一方、ヒートポンプ回路９０を冷房運転から暖房運転に切り替えると、冷媒が流れる方向が逆転して、図２の矢印で示したように、冷媒が他端側領域Ｒ２、他方の弁口１６Ｂ、中間領域Ｒ３、一方の弁口１６Ａ、一端側領域Ｒ１の順番に流れる。すると、図２から図３の変化に示したように、中間領域Ｒ３内の可動弁体１７が冷媒に押されて下流側（この場合は、図３の上側）に移動し、下流側の弁口１６Ａに遊嵌された当接シャフト１７Ｄが、可動弁体１７と一端側感圧部２０Ａとの間で突っ張り状態になる。これにより、可動弁体１７が一端側感圧部２０Ａによって位置決めされる。 On the other hand, when the heat pump circuit 90 is switched from the cooling operation to the heating operation, the direction in which the refrigerant flows is reversed, and as indicated by the arrows in FIG. 2, the refrigerant is in the other end side region R2, the other valve port 16B, and the intermediate region. It flows in the order of R3, one valve port 16A, and one end side region R1. Then, as shown in the change from FIG. 2 to FIG. 3, the movable valve body 17 in the intermediate region R3 is pushed by the refrigerant and moves to the downstream side (in this case, the upper side in FIG. 3). The contact shaft 17D loosely fitted in the port 16A is in a stretched state between the movable valve body 17 and the one-end-side pressure sensitive part 20A. Thereby, the movable valve body 17 is positioned by the one-end-side pressure sensitive part 20A.

そして、冷房運転時と同様に、一端側領域Ｒ１内の冷媒圧力が比較的大きくなると、これに伴って可動弁体１７が弁口１６Ａに接近して弁開度が小さくなり、一端側領域Ｒ１内の冷媒圧力が下がる。これとは逆に、他端側領域Ｒ２内の冷媒圧力が比較的小さくなると、これに伴って可動弁体１７が弁口１６Ｂから離れて弁開度が大きくなり、他端側領域Ｒ２内の冷媒圧力が上がる。これにより、下流側の冷媒圧力を一定にすることができる。 As in the cooling operation, when the refrigerant pressure in the one end side region R1 becomes relatively large, the movable valve body 17 approaches the valve port 16A and the valve opening decreases accordingly, and the one end side region R1. The refrigerant pressure inside decreases. On the other hand, when the refrigerant pressure in the other end side region R2 becomes relatively small, the movable valve body 17 moves away from the valve port 16B and the valve opening increases accordingly. The refrigerant pressure increases. Thereby, the refrigerant pressure on the downstream side can be made constant.

このようにして、本実施形態の双方向定圧膨張弁１０によれば、冷媒の流れる向きに拘わらず、下流側の冷媒圧力を一定にすることができる。そして、本実施形態の双方向定圧膨張弁１０では、一端側及び他端側の感圧部２０Ａ，２０Ｂは、ボディ１０Ｂに固定されているので、一端側及び他端側の感圧部２０Ａ，２０Ｂ自体が、冷媒の流れる方向に応じて移動することはない。従って、従来のようにベローズの挫屈を規制しかつ伸縮可能に支持した直動支持機構が不要になる。これにより、直動支持機構の摺動抵抗の影響がなくなり、従来より正確に冷媒を一定圧力にすることが可能になる。しかも、可動弁体１７はガイド筒体１５Ａによって直動可能に案内されているので、可動弁体１７の直動位置と弁開度との対応関係が従来より安定し、この点においても、従来より正確に冷媒を一定圧力にすることが可能になる。 Thus, according to the bidirectional constant pressure expansion valve 10 of the present embodiment, the refrigerant pressure on the downstream side can be made constant regardless of the direction in which the refrigerant flows. In the bidirectional constant pressure expansion valve 10 according to the present embodiment, the pressure-sensitive portions 20A and 20B on one end side and the other end side are fixed to the body 10B. 20B itself does not move according to the direction in which the refrigerant flows. Therefore, a linear motion support mechanism that restricts the buckling of the bellows and supports the bellows so that it can be expanded and contracted is not required. Thereby, the influence of the sliding resistance of the linear motion support mechanism is eliminated, and the refrigerant can be kept at a constant pressure more accurately than in the past. In addition, since the movable valve body 17 is guided by the guide cylinder 15A so as to be capable of linear movement, the correspondence between the linear movement position of the movable valve body 17 and the valve opening is more stable than in the prior art. It becomes possible to make the refrigerant at a constant pressure more accurately.

また、本実施形態の双方向定圧膨張弁１０は、従来の双方向定圧膨張弁と異なり、感圧部２０Ａ，２０Ｂを一端側と他端側とに対にして設けたので、室内熱交換器９２Ａ側の弁口１６Ｂの冷媒圧力に対する弁開度の特性と、室外熱交換器９１Ａ側の弁口１６Ａの冷媒圧力に対する弁開度の特性とを、それぞれ別々に適した特性に設定することができる。そして、本実施形態の双方向定圧膨張弁１０では、冷房運転時における下流側の冷媒圧力を、暖房運転時における下流側の冷媒圧力より大きくなるように構成したので、冷房運転時と暖房運転時のそれぞれで最適な温度及び圧力に制御された冷媒を室外及び室内の熱交換器９１Ａ，９２Ａに供給することができる。 Further, unlike the conventional bidirectional constant pressure expansion valve, the bidirectional constant pressure expansion valve 10 of the present embodiment is provided with the pressure sensitive portions 20A and 20B in pairs on one end side and the other end side, so that the indoor heat exchanger The characteristic of the valve opening degree with respect to the refrigerant pressure of the 92A side valve opening 16B and the characteristic of the valve opening degree with respect to the refrigerant pressure of the valve opening 16A of the outdoor heat exchanger 91A side may be set to appropriate characteristics. it can. In the bidirectional constant pressure expansion valve 10 of the present embodiment, the downstream refrigerant pressure during the cooling operation is configured to be greater than the downstream refrigerant pressure during the heating operation, so that the cooling operation and the heating operation are performed. The refrigerant controlled to the optimum temperature and pressure can be supplied to the outdoor and indoor heat exchangers 91A and 92A.

しかも、暖房運転時に下流側に位置する一方の弁口１６Ａと当接シャフト１７Ｄとの隙間の開口面積を、他方の弁口１６Ｂと当接シャフト１７Ｄとの隙間の開口面積より広くしたので、冷媒の流量が比較的大きい暖房運転時にも、適切に対応することができる。 Moreover, since the opening area of the gap between the one valve port 16A and the contact shaft 17D located on the downstream side during the heating operation is made larger than the opening area of the gap between the other valve port 16B and the contact shaft 17D, It is possible to appropriately cope with the heating operation with a relatively large flow rate.

さらに、冷房運転時に下流側に位置する他端側感圧部２０Ｂの弾性係数と、暖房運転時時に下流側に位置する一端側感圧部２０Ａの弾性係数とを異ならせて、冷媒圧力及び冷媒流量が異なる冷房運転時と暖房運転時のそれぞれにおいて最適な弁のリフト特性を得ることができる。 Further, the refrigerant pressure and the refrigerant are changed by making the elastic coefficient of the other pressure sensing section 20B located downstream during the cooling operation different from the elastic coefficient of the one pressure sensing section 20A located downstream during the heating operation. Optimal valve lift characteristics can be obtained during cooling operation and heating operation with different flow rates.

［第２実施形態］
本実施形態では、感圧ユニット５７の対向壁１３に対する位置を調節可能である点が第１実施形態異なる。具体的には、図６に示すように本実施形態の各対向壁１３には、前記第１実施形態の係止片１９に代えて、円環状突部１８の外縁部から圧入筒部５６が突出形成されている。また、感圧筒体５５は、ダイヤフラム２２を固定するためのフランジ部２１Ｆより外径が大きな圧入軸部５５Ｋが備えられ、この圧入軸部５５Ｋを圧入筒部５６に圧入することで、感圧ユニット５７を対向壁１３に対して任意の位置に保持することができる。上記以外の構成は、第１実施形態と同様であるので、重複した説明は省略する。 [Second Embodiment]
This embodiment is different from the first embodiment in that the position of the pressure-sensitive unit 57 with respect to the facing wall 13 can be adjusted. Specifically, as shown in FIG. 6, each opposing wall 13 of the present embodiment has a press-fit cylinder portion 56 from the outer edge portion of the annular projection 18 instead of the locking piece 19 of the first embodiment. Protrusions are formed. Further, the pressure-sensitive cylinder 55 is provided with a press-fit shaft portion 55K having an outer diameter larger than that of the flange portion 21F for fixing the diaphragm 22, and the pressure-sensitive shaft portion 55K is press-fitted into the press-fit cylinder portion 56 so The unit 57 can be held at an arbitrary position with respect to the facing wall 13. Since the configuration other than the above is the same as that of the first embodiment, a duplicate description is omitted.

本実施形態の感圧ユニット５７は以下のようにして位置調節される。即ち、各対向壁１３の圧入筒部５６に対して感圧ユニット５７を比較的浅く圧入し、当接シャフト１７Ｄがダイヤフラム２２に接触して各弁口１６Ａ，１６Ｂが僅かに開く位置に各感圧ユニット５７を配置して双方向定圧膨張弁１０の組付けを完成させておく。そして、例えば、他端側感圧部２０Ｂにおける感圧ユニット５７を調節するには、パイプ部材１２における他端側感圧部２０Ｂ側の開口端に流量を絞るためのオリフィス６０を取り付けると共に、中間領域Ｒ３内の圧力を検出するための図示しない圧力計を取り付ける。 The position of the pressure-sensitive unit 57 of this embodiment is adjusted as follows. That is, the pressure-sensitive unit 57 is press-fitted relatively shallowly into the press-fitting cylinder portion 56 of each opposing wall 13, and each of the sensations is located at a position where the contact shaft 17D is in contact with the diaphragm 22 and the valve ports 16A and 16B are slightly opened. The pressure unit 57 is arranged to complete the assembly of the bidirectional constant pressure expansion valve 10. For example, in order to adjust the pressure sensing unit 57 in the other pressure sensing portion 20B, an orifice 60 for restricting the flow rate is attached to the opening end of the pipe member 12 on the other pressure sensing portion 20B side, and the middle A pressure gauge (not shown) for detecting the pressure in the region R3 is attached.

この状態で、双方向定圧膨張弁１０の一端側領域Ｒ１内を所定の圧力（例えば、２ＭＰａ）にする。すると、弁口１６Ｂを通して他端側領域Ｒ２に流れ込んだ冷媒の圧力により他端側感圧部２０Ｂのダイヤフラム２２が感圧筒体２１の奥側に撓む。このとき、他端側感圧部２０Ｂ側における感圧ユニット５７の圧入筒部５６に対する圧入量が足りなければ、中間領域Ｒ３内が圧力、即ち、双方向定圧膨張弁１０の下流側の圧力が設計通りの基準圧力（例えば、０．５ＭＰａ）を下回っても弁口１６Ｂが閉じた状態に保持される。その場合、他端側感圧部２０Ｂ側の感圧ユニット５７を僅かに押し込んでから、再度、双方向定圧膨張弁１０の一端側領域Ｒ１内を所定の圧力にする。そして、中間領域Ｒ３内が設計通りの基準圧力で弁口１６Ｂが開いた状態に保持される位置まで感圧ユニット５７を押し込めばよい。そして、同様の方法で、一端側感圧部２０Ａにおける感圧ユニット５７の位置調節作業を行えばよい。 In this state, the one end side region R1 of the bidirectional constant pressure expansion valve 10 is set to a predetermined pressure (for example, 2 MPa). Then, the diaphragm 22 of the other pressure sensor 20B bends to the back side of the pressure sensing cylinder 21 due to the pressure of the refrigerant flowing into the other region R2 through the valve port 16B. At this time, if the amount of press-fitting into the press-fitting cylinder portion 56 of the pressure-sensitive unit 57 on the other end-side pressure sensing portion 20B side is insufficient, the pressure in the intermediate region R3, that is, the pressure downstream of the bidirectional constant pressure expansion valve 10 The valve port 16B is maintained in a closed state even if the pressure falls below a designed reference pressure (for example, 0.5 MPa). In that case, the pressure sensing unit 57 on the other end pressure sensing portion 20B side is slightly pushed in, and then the inside of the one end region R1 of the bidirectional constant pressure expansion valve 10 is again set to a predetermined pressure. Then, the pressure-sensitive unit 57 may be pushed to a position where the inside of the intermediate region R3 is held at a reference pressure as designed and the valve port 16B is kept open. And the position adjustment operation | work of the pressure sensitive unit 57 in the one end side pressure sensitive part 20A should just be performed by the same method.

このように双方向定圧膨張弁１０によれば、感圧ユニット５７を圧入筒部５６に圧入する位置を適宜調節することにより、双方向定圧膨張弁１０の各構成部品の寸法のばらつきによる影響を抑えて、双方向定圧膨張弁１０の品質を均一にすることができる。なお、上記した圧入作業を容易に行うために、螺子嵌合によって感圧ユニット５７を圧入筒部５６に固定してもよい。 As described above, according to the bidirectional constant pressure expansion valve 10, by appropriately adjusting the position where the pressure sensitive unit 57 is press-fitted into the press-fitting cylinder portion 56, the influence due to the dimensional variation of each component of the bidirectional constant pressure expansion valve 10 is affected. The quality of the bidirectional constant pressure expansion valve 10 can be made uniform. In order to easily perform the above-described press-fitting work, the pressure-sensitive unit 57 may be fixed to the press-fitting cylinder portion 56 by screw fitting.

［第３実施形態］
本実施形態の双方向定圧膨張弁３０は、図７に示されている。以下、前記第１実施形態と同一の構成に関しては同一の符号を付して重複した説明は省略し、第１実施形態と相違する構成に関してのみ説明する。 [Third Embodiment]
The bidirectional constant pressure expansion valve 30 of this embodiment is shown in FIG. Hereinafter, the same components as those in the first embodiment will be denoted by the same reference numerals, and redundant description will be omitted, and only components different from those in the first embodiment will be described.

図７において符号３１は、第１内壁構成体であって、前記第１実施形態における一方の対向壁１３の外径を若干小さくして、その外周面から係止突条３１Ａを張り出した構造になっている。また、符号３２は、第２内壁構成体であって、前記第１実施形態における他方の対向壁１３のうち外縁部から他端側感圧部２０Ｂと反対側に係止突片３１Ｂを張り出した構造になっている。そして、第１内壁構成体３１と第２内壁構成体３２の一端面同士を接合した状態にして、係止突片３１Ｂを内側に折り曲げて係止突条３１Ａに係合することで、第１内壁構成体３１と第２内壁構成体３２とが一体化されている。 In FIG. 7, reference numeral 31 denotes a first inner wall structure, which has a structure in which the outer diameter of one of the opposing walls 13 in the first embodiment is slightly reduced and the locking protrusion 31 A is projected from the outer peripheral surface. It has become. Reference numeral 32 denotes a second inner wall constituting body, and a locking protrusion 31B is projected from the outer edge of the other opposing wall 13 in the first embodiment to the side opposite to the other pressure sensing portion 20B. It has a structure. Then, the first end surfaces of the first inner wall constituting body 31 and the second inner wall constituting body 32 are joined to each other, the engaging protrusion 31B is bent inward and engaged with the engaging protrusion 31A. The inner wall constituting body 31 and the second inner wall constituting body 32 are integrated.

第２内壁構成体３２の中心部分には、第１内壁構成体３１との接合面に断面円形の陥没部３８が形成される一方、第１内壁構成体３１の中心部分には、円筒突部３９が形成されている。そして、陥没部３８に円筒突部３９が嵌合され、その円筒突部３９の内側が、本発明に係る中間領域Ｒ３をなし、陥没部３８と円筒突部３９の各奥壁が本発明に係る１対の対向壁１３Ｆ，１３Ｆになっている。そして、中間領域Ｒ３の内部には、本発明に係る可動弁体としての球体３３が収容されている。 A recessed portion 38 having a circular cross section is formed on the joint surface with the first inner wall constituting body 31 at the central portion of the second inner wall constituting body 32, while a cylindrical protrusion is formed at the central portion of the first inner wall constituting body 31. 39 is formed. Then, the cylindrical protrusion 39 is fitted into the depressed portion 38, the inside of the cylindrical protruding portion 39 forms an intermediate region R3 according to the present invention, and the inner walls of the depressed portion 38 and the cylindrical protruding portion 39 are included in the present invention. The pair of opposing walls 13F and 13F is used. And the spherical body 33 as a movable valve body which concerns on this invention is accommodated in the inside of intermediate | middle area | region R3.

また、一端側感圧部２０Ａ及び他端側感圧部２０Ｂの各ダイヤフラム２２には、それぞれ中心部に当接シャフト３４の一端部が固定され、当接シャフト３４の他端部がシャフト挿通孔５２、弁口１６Ａ，１６Ｂ内に配置されている。また、当接シャフト３４の一端部には大径部３４Ｄが備えられている。さらに、本実施形態のダイヤフラム固定盤５０における底壁５０Ｂは平坦になっており、シャフト挿通孔５２はその底壁５０Ｂの中心部に配置され、シャフト挿通孔５２の開口縁が過度変形防止部５３になっている。そして、この過度変形防止部５３が通常は当接シャフト３４の大径部３４Ｄに対して隙間を介して対向し、ダイヤフラム２２の過度変形を防止している。 In addition, each diaphragm 22 of the one end-side pressure sensing portion 20A and the other end-side pressure sensing portion 20B has one end portion of the contact shaft 34 fixed to the center portion, and the other end portion of the contact shaft 34 is the shaft insertion hole. 52 and the valve ports 16A and 16B. Further, a large diameter portion 34 D is provided at one end portion of the contact shaft 34. Further, the bottom wall 50B of the diaphragm fixing plate 50 of the present embodiment is flat, the shaft insertion hole 52 is disposed at the center of the bottom wall 50B, and the opening edge of the shaft insertion hole 52 is the excessive deformation preventing portion 53. It has become. The excessive deformation preventing portion 53 is normally opposed to the large diameter portion 34D of the contact shaft 34 via a gap to prevent excessive deformation of the diaphragm 22.

本実施形態の双方向定圧膨張弁３０によれば、冷媒が図７において下向きに流れると、球体３３が弁口１６Ｂ側に移動し、その弁口１６Ｂの弁座１６Ｚと球体３３との間に隙間が形成される。そして、他端側領域Ｒ２内の圧力が比較的高くなると、球体３３が弁口１６Ｂの弁座１６Ｚに接近して弁開度が小さくなり、他端側領域Ｒ２内の圧力が比較的小さくなると、球体３３が弁口１６Ｂの弁座１６Ｚから離れて弁開度が大きくなる。これにより、他端側領域Ｒ２の冷媒圧力が一定に保持される。 According to the bidirectional constant pressure expansion valve 30 of the present embodiment, when the refrigerant flows downward in FIG. 7, the sphere 33 moves to the valve port 16B side, and between the valve seat 16Z of the valve port 16B and the sphere 33. A gap is formed. When the pressure in the other end side region R2 becomes relatively high, the sphere 33 approaches the valve seat 16Z of the valve port 16B and the valve opening becomes small, and when the pressure in the other end side region R2 becomes relatively small. The spherical body 33 is separated from the valve seat 16Z of the valve port 16B, and the valve opening degree is increased. Thereby, the refrigerant | coolant pressure of other end side area | region R2 is hold | maintained uniformly.

冷媒が流れる向きが逆転した場合には、球体３３が弁口１６Ａ側に移動し、同様に、一端側領域Ｒ１内の冷媒圧力に応じて弁口１６Ａの弁開度が調節されて、一端側領域Ｒ１の冷媒圧力が一定に保持される。 When the direction in which the refrigerant flows is reversed, the sphere 33 moves to the valve port 16A side. Similarly, the valve opening degree of the valve port 16A is adjusted according to the refrigerant pressure in the one end side region R1, and the one end side The refrigerant pressure in the region R1 is kept constant.

［他の実施形態］
本発明は、前記実施形態に限定されるものではなく、例えば、以下に説明するような実施形態も本発明の技術的範囲に含まれ、さらに、下記以外にも要旨を逸脱しない範囲内で種々変更して実施することができる。 [Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

（１）前記第１〜第３の実施形態の一端側感圧部２０Ａ及び他端側感圧部２０Ｂは、ダイヤフラム２２を備えていたが、このダイヤフラム２２に代えてベローズを一端側感圧部及び他端側感圧部に設けた構成にしてもよい。 (1) The one-end-side pressure-sensitive portion 20A and the other-end-side pressure-sensitive portion 20B of the first to third embodiments include the diaphragm 22, but instead of the diaphragm 22, the bellows is replaced with the one-end-side pressure-sensitive portion. And you may make it the structure provided in the other end side pressure sensing part.

（２）前記第１〜第３の実施形態のボディ１０Ｂは、パイプ部材１２と対向壁１３（１３Ｆ）とを組み付けて構成されていたが、対向壁１３（１３Ｆ）をパイプ部材１２に一体形成したものも本発明の技術的範囲に含まれる。 (2) Although the body 10B of the first to third embodiments is configured by assembling the pipe member 12 and the opposing wall 13 (13F), the opposing wall 13 (13F) is integrally formed with the pipe member 12. These are also included in the technical scope of the present invention.

（３）図８に示すように前記第１実施形態の双方向定圧膨張弁１０からダイヤフラム固定盤５０を排除したもの、又は、図９に示すように前記第３実施形態の双方向定圧膨張弁３０からダイヤフラム固定盤５０を排除したものも本発明の技術的範囲に含まれる。 (3) A configuration in which the diaphragm fixing plate 50 is removed from the bidirectional constant pressure expansion valve 10 of the first embodiment as shown in FIG. 8, or a bidirectional constant pressure expansion valve of the third embodiment as shown in FIG. What excluded the diaphragm fixed board 50 from 30 is also contained in the technical scope of this invention.

（４）前記第１実施形態は、暖房運転時と冷房運転時とで下流側の冷媒圧力が異なるように構成になっていたが、上記した双方向定圧膨張弁の両端部の構成を同一にして暖房運転時と冷房運転時とで下流側の冷媒圧力が同一になるようにしてもよい。 (4) Although the first embodiment is configured such that the refrigerant pressure on the downstream side is different between the heating operation and the cooling operation, the configuration of both ends of the bidirectional constant pressure expansion valve described above is the same. Thus, the refrigerant pressure on the downstream side may be the same during the heating operation and during the cooling operation.

本発明の第１実施形態に係る双方向定圧膨張弁の側断面図Side sectional view of the bidirectional constant pressure expansion valve according to the first embodiment of the present invention. その双方向定圧膨張弁の側断面図Side sectional view of the bidirectional constant pressure expansion valve その双方向定圧膨張弁の側断面図Side sectional view of the bidirectional constant pressure expansion valve 双方向定圧膨張弁の一部を拡大した側断面図A side sectional view enlarging a part of the bidirectional constant pressure expansion valve ヒートポンプ回路の概念図Conceptual diagram of heat pump circuit 第２実施形態に係る双方向定圧膨張弁の側断面図Side sectional view of a bidirectional constant pressure expansion valve according to a second embodiment 第３実施形態に係る双方向定圧膨張弁の側断面図Side sectional view of a bidirectional constant pressure expansion valve according to a third embodiment 変形例の双方向定圧膨張弁の側断面図Side sectional view of a modified bi-directional constant pressure expansion valve 変形例の双方向定圧膨張弁の側断面図Side sectional view of a modified bi-directional constant pressure expansion valve 従来の双方向定圧膨張弁の側断面図Side sectional view of a conventional bidirectional constant pressure expansion valve

符号の説明Explanation of symbols

１０，３０双方向定圧膨張弁
１０Ｂボディ
１１流路
１３，１３Ｆ対向壁
１５Ａガイド筒体
１５Ｃ冷媒通過孔
１６Ａ，１６Ｂ弁口
１７可動弁体
１７Ｄ，３４当接シャフト
２０Ａ一端側感圧部
２０Ｂ他端側感圧部
２１感圧筒体
２２ダイヤフラム
３３球体
５０ダイヤフラム固定盤
５１冷媒通過孔
５２シャフト挿通孔
５３過度変形防止部
５７感圧ユニット
９０ヒートポンプ回路
９１Ａ室外熱交換器
９２Ａ室内熱交換器
Ｒ１一端側領域
Ｒ２他端側領域
Ｒ３中間領域
DESCRIPTION OF SYMBOLS 10,30 Bidirectional constant pressure expansion valve 10B Body 11 Flow path 13,13F Opposite wall 15A Guide cylinder 15C Refrigerant passage hole 16A, 16B Valve port 17 Movable valve body 17D, 34 Contact shaft 20A One end side pressure sensing part 20B The other end Side pressure sensing unit 21 Pressure sensing cylinder 22 Diaphragm 33 Sphere 50 Diaphragm fixing plate 51 Refrigerant passage hole 52 Shaft insertion hole 53 Excessive deformation prevention part 57 Pressure sensing unit 90 Heat pump circuit 91A Outdoor heat exchanger 92A Indoor heat exchanger R1 One end side Region R2 Other end region R3 Intermediate region

Claims

ヒートポンプ回路（９０）の室内熱交換器（９２Ａ）と室外熱交換器（９１Ａ）との間に接続されて冷媒が双方向に流され、下流側の冷媒圧力を一定にすることが可能な双方向定圧膨張弁（１０，３０）において、
前記冷媒の流路（１１）を内部に有したボディ（１０Ｂ）と、
前記ボディ（１０Ｂ）に設けられて、前記流路（１１）を一端側領域（Ｒ１）と中間領域（Ｒ３）と他端側領域（Ｒ２）とに区画する１対の対向壁（１３，１３Ｆ）と、
前記１対の対向壁（１３，１３Ｆ）に貫通形成されて、略同軸上に配置された１対の弁口（１６Ａ，１６Ｂ）と、
前記ボディ（１０Ｂ）に固定されて、前記一端側領域（Ｒ１）内で一方の前記弁口（１６Ａ）に対向配置され、前記一端側領域（Ｒ１）内の冷媒圧力が上昇するに従って前記一方の弁口（１６Ａ）から離れるように弾性変形する一端側感圧部（２０Ａ）と、
前記ボディ（１０Ｂ）に固定されて、前記他端側領域（Ｒ２）内で他方の前記弁口（１６Ｂ）に対向配置され、前記他端側領域（Ｒ２）内の冷媒圧力が上昇するに従って前記他方の弁口（１６Ｂ）から離れるように弾性変形する他端側感圧部（２０Ｂ）と、
前記中間領域（Ｒ３）に収容されて、前記１対の弁口（１６Ａ，１６Ｂ）の間を移動し、接近した側の前記弁口（１６Ａ，１６Ｂ）の弁開度を変更可能な可動弁体（１７，３３）と、
前記１対の弁口（１６Ａ，１６Ｂ）にそれぞれ遊嵌され、前記可動弁体（１７，３３）の位置に応じて、前記一端側又は他端側の感圧部（２０Ａ，２０Ｂ）の何れか一方と前記可動弁体（１７，３３）との間で突っ張り状態になる１対の当接シャフト（１７Ｄ，３４）とを備えたことを特徴とする双方向定圧膨張弁（１０，３０）。 Both are connected between the indoor heat exchanger (92A) and the outdoor heat exchanger (91A) of the heat pump circuit (90) so that the refrigerant flows in both directions, and the downstream refrigerant pressure can be made constant. In the constant pressure expansion valve (10, 30),
A body (10B) having a flow path (11) for the refrigerant therein;
A pair of opposing walls (13, 13F) provided in the body (10B) and partitioning the flow path (11) into one end side region (R1), an intermediate region (R3), and the other end side region (R2). )When,
A pair of valve ports (16A, 16B) that are formed through the pair of opposing walls (13, 13F) and arranged substantially coaxially;
It is fixed to the body (10B), and is disposed opposite to one of the valve ports (16A) in the one end side region (R1), and as the refrigerant pressure in the one end side region (R1) increases, One end side pressure sensing part (20A) elastically deforming away from the valve opening (16A);
It is fixed to the body (10B), is disposed opposite to the other valve port (16B) in the other end side region (R2), and the refrigerant pressure in the other end side region (R2) increases as the refrigerant pressure increases. The other end side pressure sensitive part (20B) elastically deformed away from the other valve port (16B),
A movable valve that is accommodated in the intermediate region (R3), moves between the pair of valve ports (16A, 16B), and can change the valve opening degree of the valve ports (16A, 16B) on the approaching side. Body (17, 33),
Depending on the position of the movable valve body (17, 33), either one of the pressure sensing parts (20A, 20B) on the one end side or the other end side is loosely fitted to the pair of valve ports (16A, 16B). A bidirectional constant pressure expansion valve (10, 30) comprising a pair of abutting shafts (17D, 34) that are stretched between the movable valve element (17, 33). .

前記一端側及び他端側の感圧部（２０Ａ，２０Ｂ）は、共に一端開放の感圧筒体（２１，５５）の開口端にダイヤフラム（２２）を張ってなり、前記感圧筒体（２１，５５）が前記ボディ（１０Ｂ）に固定され、前記ダイヤフラム（２２）が前記弁口（１６Ａ，１６Ｂ）に対向配置されたことを特徴とする請求項１に記載の双方向定圧膨張弁（１０，３０）。 The pressure-sensitive portions (20A, 20B) on the one end side and the other end side are each formed by placing a diaphragm (22) on the open end of a pressure-sensitive cylinder (21, 55) that is open at one end. 21. The bidirectional constant pressure expansion valve according to claim 1, wherein 21, 55) is fixed to the body (10 B), and the diaphragm (22) is disposed to face the valve port (16 A, 16 B). 10, 30).

前記感圧筒体（２１，５５）の開口縁との間に前記ダイヤフラム（２２）の外縁部を挟んで溶接されたダイヤフラム固定盤（５０）と、
前記ダイヤフラム固定盤（５０）に貫通形成されて、冷媒を通過可能とした冷媒通過孔（５１）と、
前記ダイヤフラム固定盤（５０）に貫通形成されて、前記当接シャフト（１７Ｄ，３４）が挿通したシャフト挿通孔（５２）と、
前記シャフト挿通孔（５２）の開口縁に備えられ、通常は前記ダイヤフラム（２２）に隙間を介して対向して、前記ダイヤフラム（２２）が所定量以上変形することを防止する過度変形防止部（５３）とを備えたことを特徴とする請求項２に記載の双方向定圧膨張弁（１０，３０）。 A diaphragm fixing plate (50) welded with an outer edge portion of the diaphragm (22) sandwiched between opening edges of the pressure-sensitive cylinders (21, 55);
A refrigerant passage hole (51) formed through the diaphragm fixed platen (50) to allow the refrigerant to pass through;
A shaft insertion hole (52) formed through the diaphragm fixing plate (50) and through which the contact shaft (17D, 34) is inserted;
An over-deformation preventing portion (provided at an opening edge of the shaft insertion hole (52)) and facing the diaphragm (22) through a gap to prevent the diaphragm (22) from being deformed more than a predetermined amount ( 53), the bidirectional constant pressure expansion valve (10, 30) according to claim 2.

前記感圧筒体（５５）と前記ダイヤフラム（２２）と前記ダイヤフラム固定盤（５０）とを一体化した感圧ユニット（５７）と、
前記対向壁（１３）から突出し、前記感圧ユニット（５７）を内側に圧入して任意の位置に保持可能な圧入筒部（５６）とを備えたことを特徴とする請求項３に記載の双方向定圧膨張弁（１０）。 A pressure-sensitive unit (57) in which the pressure-sensitive cylinder (55), the diaphragm (22), and the diaphragm fixing plate (50) are integrated;
The press-fitting cylinder part (56) which protrudes from the said opposing wall (13), press-fits the said pressure-sensitive unit (57) inside, and can hold | maintain in arbitrary positions is provided. Bidirectional constant pressure expansion valve (10).

一方の前記弁口（１６Ａ）と前記当接シャフト（１７Ｄ，３４）との隙間の開口面積を、他方の前記弁口（１６Ｂ）と前記当接シャフト（１７Ｄ，３４）との隙間の開口面積より広くしたことを特徴とする請求項１乃至４の何れかに記載の双方向定圧膨張弁（１０，３０）。 The opening area of the gap between the one valve port (16A) and the contact shaft (17D, 34) is the opening area of the gap between the other valve port (16B) and the contact shaft (17D, 34). The bidirectional constant pressure expansion valve (10, 30) according to any one of claims 1 to 4, characterized in that it is wider.

前記一端側又は他端側の感圧部（２０Ａ，２０Ｂ）のうち前記室内熱交換器（９２Ａ）側の感圧部（２０Ｂ）の弾性係数と、前記室外熱交換器（９１Ａ）側の感圧部（２０Ａ）の弾性係数とを異ならせたことを特徴とする請求項１乃至５の何れかに記載の双方向定圧膨張弁（１０，３０）。 The elastic coefficient of the pressure sensitive part (20B) on the indoor heat exchanger (92A) side of the pressure sensitive part (20A, 20B) on the one end side or the other end side, and the feeling on the outdoor heat exchanger (91A) side. The bidirectional constant pressure expansion valve (10, 30) according to any one of claims 1 to 5, wherein the pressure coefficient (20A) has a different elastic coefficient.

前記１対の当接シャフト（１７Ｄ）は、前記可動弁体（１７）の両端部から延設されたことを特徴とする請求項１乃至６の何れかに記載の双方向定圧膨張弁（１０）。 The bidirectional constant pressure expansion valve (10) according to any one of claims 1 to 6, wherein the pair of contact shafts (17D) extend from both ends of the movable valve body (17). ).

前記１対の当接シャフト（３４）を、前記他端側及び一端側の感圧部（２０Ａ，２０Ｂ）にそれぞれ固定し、前記可動弁体（３３）を球体（３３）で構成したことを特徴とする請求項１乃至７の何れかに記載の双方向定圧膨張弁（３０）。

The pair of abutting shafts (34) are fixed to the pressure-sensitive portions (20A, 20B) on the other end side and the one end side, respectively, and the movable valve body (33) is configured by a spherical body (33). A bidirectional constant pressure expansion valve (30) according to any of the preceding claims, characterized in that it is characterized in that