JPH08284842A - Discharge capacity control method and device for displacement type reciprocating compressor - Google Patents
Discharge capacity control method and device for displacement type reciprocating compressorInfo
- Publication number
- JPH08284842A JPH08284842A JP8806695A JP8806695A JPH08284842A JP H08284842 A JPH08284842 A JP H08284842A JP 8806695 A JP8806695 A JP 8806695A JP 8806695 A JP8806695 A JP 8806695A JP H08284842 A JPH08284842 A JP H08284842A
- Authority
- JP
- Japan
- Prior art keywords
- discharge capacity
- discharge
- cylinder
- unloader
- capacity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2600/00—Control issues
- F25B2600/25—Control of valves
- F25B2600/2521—On-off valves controlled by pulse signals
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、容積形往復圧縮機の吐
出し容量制御方法および装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge capacity control method and apparatus for a positive displacement reciprocating compressor.
【０００２】[0002]
【従来の技術】一般に、この種の容積形往復圧縮機で
は、最大使用量に対して十分となるように吐出し容量を
電動機の回転数によって定めている為、一定回転数のも
とでは、使用量が減少した際の吐出し容量の調節に工夫
を要する。2. Description of the Related Art Generally, in this type of positive-displacement reciprocating compressor, the discharge capacity is determined by the rotation speed of the electric motor so that the discharge capacity is sufficient for the maximum usage amount. It is necessary to devise to adjust the discharge capacity when the usage amount decreases.
【０００３】従来、吐出し容量の調節を行うための制御
方式としては、アンローダ方式やバイパス方式などがあ
る。Conventionally, as a control system for adjusting the discharge capacity, there are an unloader system and a bypass system.
【０００４】アンローダ方式は、シリンダの吸入弁を外
部より強制的に操作して開状態とし、シリンダ内で圧縮
仕事ができない様にすることにより吐出し容量を調節す
る方式である。The unloader system is a system for adjusting the discharge capacity by forcibly operating the intake valve of the cylinder from the outside to open it so that compression work cannot be performed in the cylinder.
【０００５】一方、バイパス方式は、不要な圧縮媒体を
外部に放出するか、あるいはバイパスして最終吐出ライ
ンから吸入ラインへ戻すことにより吐出し容量を調節す
る方式である。On the other hand, the bypass system is a system in which the discharge capacity is adjusted by discharging unnecessary compression medium to the outside or by bypassing and returning from the final discharge line to the suction line.
【０００６】また、両者を併用する場合には、アンロー
ダ方式とバイパス方式とを個別に制御していた。Further, when both are used in combination, the unloader system and the bypass system are individually controlled.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら、従来に
おける容積形往復圧縮機の吐出し容量の制御には、以下
のような問題点があった。However, the conventional control of the discharge capacity of the positive displacement reciprocating compressor has the following problems.
【０００８】アンローダ方式の場合には吐出し容量の調
節が多段階になるという問題点がある。In the case of the unloader method, there is a problem that the discharge capacity is adjusted in multiple stages.
【０００９】図９乃至図１１に、アンローダ方式による
１気筒の場合の吐出し容量調節装置の概略構成を示す。
図９に示すように上吸入弁１０３及び下吸入弁１０４の
両方共に弁閉状態であるときは１００％の負荷運転とな
り、図１０に示すように上吸入弁１０３が閉状態で下吸
入弁１０４が開状態であれば５０％の負荷運転となり、
図１１に示すように上吸入弁１０３及び下吸入弁１０４
の両方共に弁開状態であるときは０％の負荷運転とな
る。9 to 11 show a schematic structure of a discharge capacity adjusting device in the case of one cylinder by an unloader system.
When both the upper intake valve 103 and the lower intake valve 104 are closed as shown in FIG. 9, the load operation is 100%, and as shown in FIG. 10, the upper intake valve 103 is closed and the lower intake valve 104 is closed. If is open, 50% load operation,
As shown in FIG. 11, an upper intake valve 103 and a lower intake valve 104
When both are open, the load operation is 0%.
【００１０】このように１気筒では吐出し容量を０％、
５０％、１００％の３段階にしか切り換えられない。ま
た、２気筒にしても、１気筒の吐出し容量制御との組み
合せにより、０％、２５％、５０％、７５％、１００％
の５段階にしか切り換えられない。しかし一方で、弁開
放時には負荷が低減するので省エネルギーの効果があ
る。In this way, in one cylinder, the discharge capacity is 0%,
It can only be switched to 3 levels of 50% and 100%. Also, even if there are two cylinders, 0%, 25%, 50%, 75%, 100% can be obtained by combining with the discharge capacity control of one cylinder.
You can only switch to 5 steps. On the other hand, however, the load is reduced when the valve is opened, which has the effect of saving energy.
【００１１】また、バイパス方式の場合は吐出し容量を
無段階に調節する事が可能であるが、最終吐出ラインか
ら吸入ラインへ吐出し容量の一部を戻すので、圧縮機自
体は常に全負荷運転であり動力低減はない。そのため省
エネルギーの効果は得られないという問題点がある。Further, in the case of the bypass system, the discharge capacity can be adjusted steplessly, but since a part of the discharge capacity is returned from the final discharge line to the suction line, the compressor itself is always under full load. It is an operation and there is no power reduction. Therefore, there is a problem that the effect of energy saving cannot be obtained.
【００１２】さらに、これら両者を併用する場合は、ア
ンローダ方式とバイパス方式とを個別に制御しているた
め、必要に応じた吐出し容量を０％から１００％まで連
続変化させる事が不可能であり、また切り換え時には圧
力変動が多く発生していた。加えて、吐出し容量を調節
するのに圧縮機の電動機（モーター）の回転数を制御し
て行う方式もあるが、往復圧縮機の場合はトルク変動が
生じるため製作が難しく一般的に採用されていないのが
実情である。Further, when both of them are used in combination, the unloader system and the bypass system are individually controlled, so that it is impossible to continuously change the discharge capacity from 0% to 100% as needed. There was a lot of pressure fluctuation at the time of switching. In addition, there is also a method of controlling the rotation speed of the compressor electric motor to adjust the discharge capacity, but in the case of a reciprocating compressor, it is difficult to manufacture because it causes torque fluctuations and is generally adopted. The reality is not.
【００１３】本発明は、上述した従来技術の問題点に鑑
み、省エネルギー化を図り、かつ吐出し容量を無段階に
調節することができる容積形往復圧縮機の吐出し容量制
御方法および装置を提供することを目的としている。In view of the above-mentioned problems of the prior art, the present invention provides a discharge capacity control method and apparatus for a positive-displacement reciprocating compressor, which is capable of saving energy and continuously adjusting the discharge capacity. The purpose is to do.
【００１４】[0014]
【課題を解決するための手段】上記目的を達成するため
に第１発明は、シリンダより吐き出される一定の吐出し
容量を、アンローダ機構によりシリンダの吸入弁を強制
的に開閉操作して調節する容積形往復圧縮機の吐出し容
量制御方法において、最終吐出ラインの圧力変動を検出
し、この検出結果によりアンローダ機構による吸入弁の
開閉操作間隔を時分割制御することにより吐出し容量を
自動的に無段階調節することを特徴とする。In order to achieve the above object, a first invention is a volume for adjusting a constant discharge capacity discharged from a cylinder by forcibly opening and closing an intake valve of the cylinder by an unloader mechanism. In the discharge capacity control method of the reciprocating compressor, the discharge capacity is automatically adjusted by detecting the pressure fluctuation in the final discharge line and controlling the opening / closing operation interval of the intake valve by the unloader mechanism in a time-division manner based on the detection result. It is characterized in that it is adjusted in stages.
【００１５】また、第２発明は、吸入弁と吐出弁を有す
るシリンダと、該シリンダ内でピストンを一定の回転数
で往復運動させる電動機と、前記シリンダの吸入弁を強
制的に開閉操作するアンローダ機構とを備えた容積形往
復圧縮機の吐出し容量制御装置において、最終吐出ライ
ンの圧力変動を検出する圧力検出器を有し、前記圧力検
出器の検出結果により前記アンローダ機構による吸入弁
の開閉操作間隔を時分割制御するものであることを特徴
とする。A second invention is a cylinder having a suction valve and a discharge valve, an electric motor for reciprocating a piston in the cylinder at a constant rotation speed, and an unloader for forcibly opening and closing the suction valve of the cylinder. A discharge capacity control device for a positive-displacement reciprocating compressor including a mechanism, which has a pressure detector for detecting the pressure fluctuation of the final discharge line, and which opens and closes the suction valve by the unloader mechanism based on the detection result of the pressure detector. It is characterized in that the operation interval is time-division controlled.
【００１６】この吐出し容量制御装置においては、前記
シリンダの吐出弁と前記最終吐出ラインの間にストレー
ジタンクが配設されているものが好ましい。In this discharge capacity control device, it is preferable that a storage tank is arranged between the discharge valve of the cylinder and the final discharge line.
【００１７】[0017]
【作用】上記のとおりに構成された本発明では、最大使
用量に対して十分な吐出し容量が電動機の回転数によっ
て一定に定められている。このような状態で使用量が減
少して最終吐出ラインの吐出し圧力が上昇すると、圧力
検出器がその圧力値を検出して制御装置に出力する。制
御装置では、検出された圧力値により、最終吐出ライン
の吐出し圧力が一定（設定値）になるような負荷容量を
算出する。この算出結果に基づき、アンローダ機構によ
る吸入弁の開閉操作間隔が時分割制御（ＰＷＭ制御）さ
れる。In the present invention constructed as described above, a sufficient discharge capacity with respect to the maximum usage amount is set to be constant depending on the rotation speed of the electric motor. When the usage amount decreases and the discharge pressure of the final discharge line rises in such a state, the pressure detector detects the pressure value and outputs it to the control device. The control device calculates a load capacity based on the detected pressure value so that the discharge pressure of the final discharge line becomes constant (set value). Based on the calculation result, the opening / closing operation interval of the intake valve by the unloader mechanism is time-division controlled (PWM control).
【００１８】このように、使用量が減少して吐出し圧力
が上昇すれば自動的に吐出し容量を無段階調節して圧力
を一定に保つので、動力の節約を図ることが可能にな
る。In this way, when the usage amount decreases and the discharge pressure rises, the discharge capacity is automatically adjusted steplessly to keep the pressure constant, so that it is possible to save power.
【００１９】[0019]
【実施例】以下、本発明の実施例について図面を参照し
て説明する。Embodiments of the present invention will be described below with reference to the drawings.
【００２０】（第１の実施例）図１は本発明の容積形往
復圧縮装置の吐出し容量制御装置の第１実施例を示す概
略構成図である。(First Embodiment) FIG. 1 is a schematic block diagram showing a first embodiment of a discharge capacity control device of a positive displacement reciprocating compression device of the present invention.
【００２１】本実施例における容積形往復圧縮装置の吐
出し容量制御装置は、図１に示すように、ベッド１およ
びフレーム２により設置された１気筒の複動形シリンダ
３と、シリンダ３内でピストンを一定に往復運動させる
ための、フライホイール４を持つ電動機５とを備えてい
る。As shown in FIG. 1, the discharge capacity control device of the positive-displacement reciprocating compressor according to the present embodiment includes a double-acting cylinder 3 of one cylinder installed by a bed 1 and a frame 2 and a cylinder 3. An electric motor 5 having a flywheel 4 for causing the piston to reciprocate constantly.
【００２２】シリンダ３の後端付近の一側部には、ピス
トンの先端側への押し込み工程時に開になり吸入ライン
６よりガスをシリンダ室内に導く下吸入弁８が設けら
れ、その他側部には、ピストンの後端側への引き込み工
程時に開になりシリンダ室内から吐出ライン７に圧縮ガ
スを吐き出す下吐出し弁が設けられている。On one side near the rear end of the cylinder 3, there is provided a lower suction valve 8 which is opened during the process of pushing the piston toward the front end and guides gas from the suction line 6 into the cylinder chamber, and on the other side. Is provided with a lower discharge valve that opens during the process of drawing the piston to the rear end side and discharges the compressed gas from the cylinder chamber to the discharge line 7.
【００２３】同様にシリンダ３の先端付近の一側部に
は、ピストンの先端側への引き込み工程時に開となり吸
入ライン６よりガスをシリンダ室内に導く上吸入弁９が
設けられ、その他側部には、ピストンの先端側への押し
込み工程時に開になりシリンダ室内から吐出ライン７に
圧縮ガスを吐き出す上吐き出し弁が設けられている。Similarly, on one side near the tip of the cylinder 3, there is provided an upper suction valve 9 which is opened during the process of drawing the piston toward the tip side and guides gas from the suction line 6 into the cylinder chamber, and the other side. Is provided with an upper discharge valve that opens during the process of pushing the piston toward the tip side and discharges the compressed gas from the cylinder chamber to the discharge line 7.
【００２４】下吸入弁８は下エアーシリンダ１０により
強制的に開操作される下アンローダ機構になっており、
同様に上吸入弁８も上エアーシリンダ１１により強制的
に開操作される上アンローダ機構になっている。The lower intake valve 8 has a lower unloader mechanism which is forcibly opened by a lower air cylinder 10.
Similarly, the upper intake valve 8 also has an upper unloader mechanism that is forcibly opened by the upper air cylinder 11.
【００２５】また、吐出ライン７には吐出し圧力を検出
するための圧力検出器１２が設置されている。Further, the discharge line 7 is provided with a pressure detector 12 for detecting the discharge pressure.
【００２６】下エアーシリンダ１０及び上エアーシリン
ダ１１、圧力検出器１２は制御装置１３と接続されてい
る。The lower air cylinder 10, the upper air cylinder 11, and the pressure detector 12 are connected to the controller 13.
【００２７】本実施例の容積形往復圧縮装置では、電動
機の回転数で決定される吐出し容量の圧縮ガスを供給し
ているので、使用量が減少すると吐出ライン７にて圧縮
ガスの圧力が上昇する。そのため制御装置１３は、圧力
検出器１２で吐出し圧力を測定し、この測定値に基づい
て下エアーシリンダ１０及び上エアーシリンダ１１によ
る下吸入弁８及び上吸入弁９の開閉を操作することによ
り吐出し容量を調節して吐出し圧力を一定に保つ事ので
きるフィードバック制御の構成になっている。このフィ
ードバック制御の構成を図２にブロック線図として示
す。In the positive-displacement reciprocating compressor of this embodiment, since the compressed gas having the discharge capacity determined by the rotation speed of the electric motor is supplied, the pressure of the compressed gas in the discharge line 7 is reduced when the usage amount decreases. To rise. Therefore, the control device 13 measures the discharge pressure with the pressure detector 12, and operates the lower intake valve 8 and the upper intake valve 9 to open and close by the lower air cylinder 10 and the upper air cylinder 11 based on the measured values. It has a feedback control structure capable of adjusting the discharge volume and keeping the discharge pressure constant. The configuration of this feedback control is shown as a block diagram in FIG.
【００２８】上記の制御装置１３では、図２に示すよう
に、調節計がプロセス変量に基づいて比較・演算を行
い、アンローダ機構に吸入弁を開操作させる操作信号
（パルス信号）を出力する。アンローダ機構により吸入
弁が前記操作信号に対応する操作量（パルス間隔）で操
作され、この状態で吐出しプロセスが行われる。さら
に、吐出しプロセスにおいて外乱を含んだ実際の制御量
によりプロセス変量が検出され、再び調節計にフィード
バックされる。このような制御装置１３では、吐出し容
量が常に使用量の変化に応じてアンローダ機構の操作に
より自動調節されている。In the control device 13, as shown in FIG. 2, the controller performs comparison and calculation based on the process variable, and outputs an operation signal (pulse signal) to the unloader mechanism to open the intake valve. The unloader mechanism operates the suction valve with an operation amount (pulse interval) corresponding to the operation signal, and the discharge process is performed in this state. Further, the process variable is detected by the actual controlled variable including the disturbance in the discharging process, and is fed back to the controller again. In such a control device 13, the discharge capacity is always automatically adjusted by operating the unloader mechanism according to the change in the usage amount.
【００２９】次に、上記の圧力検出器１２の測定値によ
るアンローダ機構の制御操作について説明する。Next, the control operation of the unloader mechanism based on the measured value of the pressure detector 12 will be described.
【００３０】図３は、本発明の第１の実施例による吐出
し容量の自動調節を説明するための図であり、（Ａ）は
負荷容量と容量調節の関係を示し、（Ｂ）は負荷容量と
上アンローダによる操作との関係を示し、（Ｃ）は負荷
容量と下アンローダによる操作との関係を示している。
図４は、第１の実施例のアンローダ機構の動作を示す図
である。3A and 3B are views for explaining the automatic adjustment of the discharge capacity according to the first embodiment of the present invention. FIG. 3A shows the relationship between the load capacity and the capacity adjustment, and FIG. The relationship between the capacity and the operation by the upper unloader is shown, and (C) shows the relationship between the load capacity and the operation by the lower unloader.
FIG. 4 is a diagram showing the operation of the unloader mechanism of the first embodiment.
【００３１】本実施例の負荷容量と容量調節とは、図３
（Ａ）に示すように正比例の関係にあり、無段階の容量
調節になっている。すなわち、図３（Ｂ）および図３
（Ｃ）に示すように、負荷容量が０％を越え５０％まで
の場合は、上アンローダの吸入弁の開閉操作を時分割制
御（ＰＷＭ制御）し、下アンローダの吸入弁を開（ノン
ロード）の状態にすることにより無段階に調節される。
また、負荷容量が５０％を越え１００％までの場合は、
上アンローダの吸入弁を閉（ロード）の状態とし、下ア
ンローダの吸入弁の開閉操作を時分割制御（ＰＷＭ制
御）することにより無段階に調節される。The load capacity and capacity adjustment of this embodiment are shown in FIG.
As shown in (A), there is a direct proportional relationship, and the capacity is adjusted steplessly. That is, FIG. 3 (B) and FIG.
As shown in (C), when the load capacity exceeds 0% to 50%, the opening / closing operation of the intake valve of the upper unloader is time-division controlled (PWM control), and the intake valve of the lower unloader is opened (non-load). It can be adjusted steplessly by setting.
If the load capacity exceeds 50% and reaches 100%,
The intake valve of the upper unloader is closed (loaded), and the opening / closing operation of the intake valve of the lower unloader is time-divisionally controlled (PWM control) to adjust continuously.
【００３２】時分割制御（ＰＷＭ制御）は、吸入弁を開
閉操作させる操作信号のパルス幅を変更することにより
行われる。すなわち、図４に示すようにロード（閉）状
態とアンロード（開）状態とを加算したパスル間隔から
なる周期Ｔを繰返し、その周期Ｔのうちノンロード
（開）状態とするパスル間隔を変更することにより、ア
ンローダの操作が時分割制御される。The time division control (PWM control) is performed by changing the pulse width of the operation signal for opening and closing the intake valve. That is, as shown in FIG. 4, a cycle T including a pulse interval obtained by adding a load (closed) state and an unload (open) state is repeated, and a pulse interval for changing the cycle to a non-load (open) state is changed. Thus, the operation of the unloader is time-division controlled.
【００３３】図５はアンローダ機構による吐出し容量の
自動調節を示すフローチャートである。FIG. 5 is a flow chart showing the automatic adjustment of the discharge volume by the unloader mechanism.
【００３４】図５に示すように、容量制御が開始される
と、初期設定に基づいて演算が行われる。すなわち、本
実施例では吐出ラインにおける吐出し圧力の変動に応じ
た出力を算出する。例えば、使用量が減少して最終吐出
ラインの吐出し圧力が上昇すればこの圧力上昇を一定に
保つ事のできる負荷容量が何％であるかを算出する。そ
の演算結果が０％の場合は、上アンローダをノンロード
（吸入弁開状態）とし、下アンローダもノンロード（吸
入弁開状態）とする。As shown in FIG. 5, when the capacity control is started, the calculation is performed based on the initial setting. That is, in this embodiment, the output according to the fluctuation of the discharge pressure in the discharge line is calculated. For example, if the usage amount decreases and the discharge pressure of the final discharge line rises, what percentage of the load capacity can keep this pressure rise constant is calculated. When the calculation result is 0%, the upper unloader is set to non-load (intake valve open state) and the lower unloader is set to non-load (intake valve open state).
【００３５】演算結果が０％を越え５０％以下の場合
は、上アンローダをその演算結果の２倍の出力で操作
し、下アンローダをノンロード（吸入弁開状態）とす
る。When the calculation result is more than 0% and 50% or less, the upper unloader is operated with twice the output of the calculation result, and the lower unloader is non-loaded (intake valve open state).
【００３６】さらに演算結果が５０％を越え１００％以
下の場合は、上アンローダをロード（吸入弁閉状態）と
し、下アンローダをその演算結果から５０を減算した値
の２倍の出力で操作する。When the calculation result is more than 50% and 100% or less, the upper unloader is set to the load (intake valve closed state) and the lower unloader is operated with an output twice the value obtained by subtracting 50 from the calculation result. .
【００３７】上述したように本実施例は常に一つのアン
ローダによる時分割制御により、吐出し容量の自動調節
を行っている。As described above, in this embodiment, the discharge capacity is automatically adjusted by the time-division control by one unloader.
【００３８】（第２の実施例）図６は本発明の容積形往
復圧縮装置の吐出し容量制御装置の第２実施例を示す概
略構成図である。ここでは、第１の実施例と異なる部分
を主に説明する。(Second Embodiment) FIG. 6 is a schematic structural view showing a second embodiment of the discharge capacity control device of the positive displacement reciprocating compression device of the present invention. Here, the part different from the first embodiment will be mainly described.
【００３９】図６に示すシリンダ１３より吐き出された
圧縮ガスは、吐出ライン１７ａ、ストレージタンク２４
および吐出ライン１７ｂを通過する構成となっている。
ストレージタンク２４は、シリンダ内のピストンによる
吸引、吐出しの繰返し操作による管路の圧力変動を吸収
する役割を有する。そして、吐出ライン１７ｂには圧力
検出器２２が設置され、圧力検出器２２による測定結果
が制御装置２３に出力される構成になっている。The compressed gas discharged from the cylinder 13 shown in FIG. 6 is discharged through the discharge line 17a and the storage tank 24.
And, it is configured to pass through the discharge line 17b.
The storage tank 24 has a role of absorbing pressure fluctuations in the pipeline due to repeated operations of suction and discharge by the piston in the cylinder. A pressure detector 22 is installed on the discharge line 17b, and the measurement result of the pressure detector 22 is output to the control device 23.
【００４０】この圧力検出器２２の検出結果に基づく、
制御装置２３による下吸入弁１８および上吸入弁１９の
開閉操作を図７および図８に示す。Based on the detection result of the pressure detector 22,
Opening and closing operations of the lower intake valve 18 and the upper intake valve 19 by the control device 23 are shown in FIGS. 7 and 8.
【００４１】図７は、本発明の第２の実施例による吐出
し容量の自動調節を説明するための図であり、（Ａ）は
負荷容量と容量調節の関係を示し、（Ｂ）は負荷容量と
上アンローダによる操作との関係を示し、（Ｃ）は負荷
容量と下アンローダによる操作との関係を示している。
図８は、第２実施例のアンローダ機構の動作を示す図で
ある。FIG. 7 is a diagram for explaining the automatic adjustment of the discharge capacity according to the second embodiment of the present invention, (A) shows the relationship between the load capacity and the capacity adjustment, and (B) shows the load. The relationship between the capacity and the operation by the upper unloader is shown, and (C) shows the relationship between the load capacity and the operation by the lower unloader.
FIG. 8 is a diagram showing the operation of the unloader mechanism of the second embodiment.
【００４２】本実施例の負荷容量と容量調節とは、図７
（Ａ）に示すように正比例の関係にあり、第１の実施例
と同様に無段階の容量調節になっている。すなわち、図
７（Ｂ）および図７（Ｃ）に示すように、負荷容量が０
％を越え１００％まで、上アンローダの吸入弁の開閉操
作と下アンローダの吸入弁の開閉操作とを常時交互に時
分割制御（ＰＷＭ制御）することにより無段階に調節さ
れる。The load capacity and capacity adjustment of this embodiment are shown in FIG.
As shown in (A), there is a direct proportional relationship, and the capacity is adjusted steplessly as in the first embodiment. That is, as shown in FIGS. 7B and 7C, the load capacity is 0
%, Up to 100% is continuously adjusted by alternately performing time division control (PWM control) of opening / closing operation of the intake valve of the upper unloader and opening / closing operation of the intake valve of the lower unloader.
【００４３】図８に示すように、上アンローダの操作に
おける時分割制御（ＰＷＭ制御）は、ロード（閉）状態
とアンロード（開）状態とを加算したパスル間隔からな
る周期Ｔを２回繰返し、その周期Ｔのうちアンロード
（開）状態とするパスル間隔を変更することにより行わ
れ、下アンローダの操作における時分割制御（ＰＷＭ制
御）は、上アンローダの時分割制御（ＰＷＭ制御）と同
様の制御でＴ／２位相をずらして行われている。As shown in FIG. 8, in the time division control (PWM control) in the operation of the upper unloader, the cycle T consisting of the pulse interval obtained by adding the load (closed) state and the unload (open) state is repeated twice. , The time division control (PWM control) in the operation of the lower unloader is the same as the time division control (PWM control) of the upper unloader. The control is performed by shifting the T / 2 phase.
【００４４】これにより、第１の実施例に比べて細かい
時分割制御が可能となり出力が安定する。As a result, finer time division control can be performed as compared with the first embodiment, and the output becomes stable.
【００４５】また、上述した実施例では１気筒の場合を
例に採って説明しているが、２気筒を並列にした場合は
さらに細かい時分割制御（ＰＷＭ制御）が可能となり出
力が安定する。In the above embodiment, the case of one cylinder is described as an example, but when two cylinders are arranged in parallel, finer time division control (PWM control) is possible and the output is stable.
【００４６】[0046]
【発明の効果】以上説明したように本発明は、最終吐出
ラインの圧力変動の検出結果によりアンローダ機構によ
る吸入弁の開閉操作間隔を時分割制御（ＰＷＭ制御）す
ることにより、吐出し容量の調節を使用量に応じて無段
階に行なうことができる。As described above, according to the present invention, the discharge capacity is adjusted by time-division control (PWM control) of the opening / closing operation interval of the intake valve by the unloader mechanism based on the detection result of the pressure fluctuation of the final discharge line. Can be performed steplessly depending on the amount used.
【００４７】また、アンローダ方式による吐出し容量の
制御であるためエネルギーの効率が向上するという効果
も奏する。Further, since the discharge capacity is controlled by the unloader system, there is an effect that the energy efficiency is improved.
【図１】本発明の容積形往復圧縮装置の吐出し容量制御
装置の第１実施例を示す概略構成図である。FIG. 1 is a schematic configuration diagram showing a first embodiment of a discharge capacity control device of a positive displacement type reciprocating compression device of the present invention.
【図２】本発明の第１の実施例における吐出し容量の自
動制御の概念的な構成を示すブロック線図である。FIG. 2 is a block diagram showing a conceptual configuration of automatic control of a discharge volume in the first embodiment of the present invention.
【図３】本発明の第１の実施例による吐出し容量の自動
調節を説明するための図であり、（Ａ）は負荷容量と容
量調節の関係を示し、（Ｂ）は負荷容量と上アンローダ
の操作の関係を示し、（Ｃ）は負荷容量と下アンローダ
の操作の関係を示している。FIG. 3 is a diagram for explaining the automatic adjustment of the discharge capacity according to the first embodiment of the present invention, where (A) shows the relationship between the load capacity and the capacity adjustment, and (B) shows the load capacity and the above. The relationship of the operation of the unloader is shown, and (C) shows the relationship of the load capacity and the operation of the lower unloader.
【図４】本発明の第１実施例のアンローダ機構の動作を
示す図である。FIG. 4 is a diagram showing an operation of the unloader mechanism of the first embodiment of the present invention.
【図５】本発明のアンローダ機構による吐出し容量の自
動調節を示すフローチャートである。FIG. 5 is a flowchart showing automatic adjustment of the discharge capacity by the unloader mechanism of the present invention.
【図６】本発明の容積形往復圧縮装置の吐出し容量制御
装置の第２実施例を示す概略構成図である。FIG. 6 is a schematic configuration diagram showing a second embodiment of the discharge capacity control device of the positive displacement reciprocating compression device of the present invention.
【図７】本発明の第２の実施例による吐出し容量の自動
調節を説明するための図であり、（Ａ）は負荷容量と容
量調節の関係を示し、（Ｂ）は負荷容量と上アンローダ
による操作との関係を示し、（Ｃ）は負荷容量と下アン
ローダによる操作との関係を示している。7A and 7B are views for explaining the automatic adjustment of the discharge capacity according to the second embodiment of the present invention, in which FIG. 7A shows the relationship between the load capacity and the capacity adjustment, and FIG. The relationship with the operation by the unloader is shown, and (C) shows the relationship between the load capacity and the operation by the lower unloader.
【図８】本発明の第２実施例のアンローダ機構の動作を
示す図である。FIG. 8 is a view showing the operation of the unloader mechanism of the second embodiment of the present invention.
【図９】アンローダ方式による１気筒の場合の吐出し容
量調節装置の１００％負荷運転の概略構成を示す図であ
る。FIG. 9 is a diagram showing a schematic configuration of 100% load operation of a discharge capacity adjusting device in the case of one cylinder by an unloader method.
【図１０】アンローダ方式による１気筒の場合の吐出し
容量調節装置の５０％負荷運転の概略構成を示す図であ
る。FIG. 10 is a diagram showing a schematic configuration of 50% load operation of a discharge capacity adjusting device in the case of one cylinder by an unloader system.
【図１１】アンローダ方式による１気筒の場合の吐出し
容量調節装置の０％負荷運転の概略構成を示す図であ
る。FIG. 11 is a diagram showing a schematic configuration of 0% load operation of the discharge capacity adjusting device in the case of one cylinder by an unloader system.
１、１１ ベッド ２、１２ フレーム ３、１３ シリンダ ４、１４ フライホイール ５、１５ 電動機 ６、１６ 吸入ライン ７、１７ａ、１７ｂ 吐出ライン ８、１８ 下吸入弁 ９、１９ 上吸入弁 １０、２０ 下エアーシリンダ １１、２１ 上エアーシリンダ １２、２２ 圧力検出器 １３、２３ 制御装置 ２４ ストレージタンク 1, 11 Bed 2, 12 Frame 3, 13 Cylinder 4, 14 Flywheel 5, 15 Electric motor 6, 16 Suction line 7, 17a, 17b Discharge line 8, 18 Lower suction valve 9, 19 Upper suction valve 10, 20 Lower air Cylinder 11, 21 Upper air cylinder 12, 22 Pressure detector 13, 23 Control device 24 Storage tank
─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成７年５月１１日[Submission date] May 11, 1995
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００４３[Correction target item name] 0043
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００４３】図８に示すように、上アンローダの操作に
おける時分割制御（ＰＷＭ制御）は、ロード（閉）状態
とアンロード（開）状態とを加算したパスル間隔からな
る周期Ｔを繰返し、その周期Ｔのうちアンロード（開）
状態とするパスル間隔を変更することにより行われ、下
アンローダの操作における時分割制御（ＰＷＭ制御）
は、上アンローダの時分割制御（ＰＷＭ制御）と同様の
制御でＴ／２位相をずらして行われている。As shown in FIG. 8, a time sharing control in the operation of the above unloader (PWM control) is, repeatedly a period T consisting Pasuru interval obtained by adding the load (closed) and unloading (open) state, Unload (open) in the cycle T
Time division control (PWM control) in the operation of the lower unloader, which is performed by changing the pulse interval for the state.
Is performed by shifting the T / 2 phase by a control similar to the time division control (PWM control) of the upper unloader.
Claims (3)
容量を、アンローダ機構によりシリンダの吸入弁を強制
的に開閉操作して調節する容積形往復圧縮機の吐出し容
量制御方法において、 最終吐出ラインの圧力変動を検出し、この検出結果によ
りアンローダ機構による吸入弁の開閉操作間隔を時分割
制御することにより吐出し容量を自動的に無段階調節す
ることを特徴とする吐出し容量制御方法。1. A discharge capacity control method for a positive-displacement reciprocating compressor, wherein a constant discharge capacity discharged from a cylinder is adjusted by forcibly opening and closing an intake valve of the cylinder by an unloader mechanism. A discharge capacity control method characterized in that pressure fluctuations are detected, and the discharge capacity is automatically and continuously adjusted by time-divisionally controlling the opening / closing operation interval of an intake valve by an unloader mechanism based on the detection result.
シリンダ内でピストンを一定の回転数で往復運動させる
電動機と、前記シリンダの吸入弁を強制的に開閉操作す
るアンローダ機構とを備えた容積形往復圧縮機の吐出し
容量制御装置において、 最終吐出ラインの圧力変動を検出する圧力検出器を有
し、 前記圧力検出器の検出結果により前記アンローダ機構に
よる吸入弁の開閉操作間隔を時分割制御するものである
ことを特徴とする吐出し容量制御装置。2. A cylinder having a suction valve and a discharge valve, an electric motor for reciprocating a piston in the cylinder at a constant rotation speed, and an unloader mechanism for forcibly opening and closing the suction valve of the cylinder. The discharge capacity control device of the positive displacement reciprocating compressor has a pressure detector for detecting the pressure fluctuation of the final discharge line, and the opening / closing operation interval of the suction valve by the unloader mechanism is time-divided according to the detection result of the pressure detector. A discharge volume control device characterized by being controlled.
インの間にはストレージタンクが配設されていることを
特徴とする請求項２に記載の吐出し容量制御装置。3. The discharge capacity control device according to claim 2, wherein a storage tank is arranged between the discharge valve of the cylinder and the final discharge line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8806695A JPH08284842A (en) | 1995-04-13 | 1995-04-13 | Discharge capacity control method and device for displacement type reciprocating compressor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8806695A JPH08284842A (en) | 1995-04-13 | 1995-04-13 | Discharge capacity control method and device for displacement type reciprocating compressor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08284842A true JPH08284842A (en) | 1996-10-29 |
Family
ID=13932488
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8806695A Pending JPH08284842A (en) | 1995-04-13 | 1995-04-13 | Discharge capacity control method and device for displacement type reciprocating compressor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08284842A (en) |
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