公开(公告)号：US5845509A

公开(公告)日：1998-12-08

申请号：US937984

申请日：1997-09-26

申请人： David N. Shaw ,  Giridhari L. Agrawal

发明人： David N. Shaw ,  Giridhari L. Agrawal

IPC分类号： F04D27/02 ,  F25B1/053 ,  F25B49/02 ,  F25B7/00 ,  F04B41/06

CPC分类号： F25B1/053 ,  F04D27/0261 ,  F25B49/022 ,  F25B2400/075 ,  F25B2400/0751 ,  F25B2600/0253 ,  Y02B30/741

摘要： A plurality of variable speed centrifugal compressors operated in parallel form an HVAC or refrigeration system. The compressors are operated at proportionally synchronized speeds throughout their range of operation.

摘要翻译： 多个并联运行的变速离心压缩机形成HVAC或制冷系统。 压缩机在整个操作范围内按比例同步的速度运行。

公开(公告)号：US5044894A

公开(公告)日：1991-09-03

申请号：US620116

申请日：1990-11-30

申请人： Michael G. Field ,  David N. Shaw

发明人： Michael G. Field ,  David N. Shaw

IPC分类号： F04C18/16 ,  F01C1/16 ,  F04B23/04 ,  F04B49/00 ,  F04B49/02 ,  F04C3/00 ,  F04C28/06 ,  F04C28/12 ,  F04C28/26

CPC分类号： F04C28/125

摘要： The slide valve and the slide stop of a screw compressor are infinitely positionable over their range of movement. Movement is achieved by fluid pressure acting across an actuating piston in combination with the fluid pressure acting on the slide valve and slide stop plus a spring bias.

公开(公告)号：US4938029A

公开(公告)日：1990-07-03

申请号：US374907

申请日：1989-07-03

申请人： David N. Shaw

发明人： David N. Shaw

IPC分类号： F25B1/10 ,  F25B5/02 ,  F25B40/02

CPC分类号： F25B40/02 ,  F25B1/10 ,  F25B5/02 ,  F25B2400/13 ,  F25B2600/2509 ,  F25B2700/2104 ,  F25B2700/21152

摘要： An economizer is connected to a fluid line connecting the first and second stages of a compressor at a point downstream of the bypass for unloading the first stage. The economizer flow controls the discharge temperature of the second stage and, in addition, coacts with the bypassing of the first stage such that all of the flow supplied to the second stage is at system suction pressure when the bypass is fully open.

公开(公告)号：US4748820A

公开(公告)日：1988-06-07

申请号：US1213

申请日：1987-01-07

申请人： David N. Shaw

发明人： David N. Shaw

IPC分类号： F25D13/00 ,  F25B1/10 ,  F25B5/00 ,  F25B5/02 ,  F25B41/04 ,  F25B49/02 ,  F25B7/00

CPC分类号： F25B5/02 ,  F25B1/10 ,  F25B41/04 ,  F25B49/022 ,  F25B5/00 ,  F25B2400/075 ,  F25B2400/13 ,  F25B2400/22 ,  F25B2600/021 ,  Y02B30/741

摘要： A unique multi-stage refrigeration system for multiple product-display cases in which each display case has a low-stage booster compressor disposed therein. Each booster compressor compresses refrigerant received from the evaporator in its display case and feeds same to a bank of high-stage compressors disposed in a remotely located equipment room. A mechanical sub-cooler is provided for controlling liquid refrigerant temperature, and an improved lubrication system is provided for balancing the distribution of lubricant throughout the system. Several modifications of the system are also shown.

摘要翻译： 一种独特的多级制冷系统，用于多个产品展示柜，其中每个展示柜具有设置在其中的低级增压压缩机。 每个增压压缩机将在显示器壳体中从蒸发器接收的制冷剂压缩并将其馈送到设置在远程设备室中的高级压缩机组。 提供了用于控制液体制冷剂温度的机械副冷却器，并且提供改进的润滑系统以平衡润滑剂在整个系统中的分布。 还显示了系统的几个修改。

公开(公告)号：US4478054A

公开(公告)日：1984-10-23

申请号：US513182

申请日：1983-07-12

申请人： David N. Shaw ,  Clifford T. Bulkley

发明人： David N. Shaw ,  Clifford T. Bulkley

IPC分类号： F04C18/16 ,  F04C28/28 ,  F04C29/02 ,  F25B1/047 ,  F25B27/00

CPC分类号： F04C29/026 ,  F25B1/047 ,  Y10S418/01

摘要： A helical screw rotary compressor for a closed loop refrigeration system such as an air conditioning system for a bus or like vehicle is connected in series with a condenser and an evaporator, in that order, with the evaporator at a raised position relative to the compressor and utilizes a vaporizable refrigerant which is miscible with a lubricating oil employed to lubricate the moving components of the screw compressor. The bus engine driven, clutch operated, helical screw rotors are mounted within parallel intersecting bores within the compressor housing. A slide valve underlies the intermeshed rotors and forms a portion of the screw compressor envelope, the rotors opening to a suction port connected to the outlet side of the evaporator above the rotors. A high pressure discharge port at one end of the intermeshed rotors leads to an auxiliary chamber bearing an unload cylinder which drives the slide valve and which opens at the top to a housing discharge port leading to the condenser. An oil separator is interposed within the auxiliary chamber above the unload cylinder. An oil drain passage leads from the auxiliary chamber to an oversized oil sump within the housing beneath the rotors. The slide valve slides in a recess within the casing underlying the rotors. On the suction port side of the recess, a further drain passage leads through a drainage check valve to the sump. This structural arrangement permits all condensed refrigerant and the oil to return by gravity flow to the oil sump whose capacity is at least 1.5 times the volume of the normal oil charge for the system. Condensed refrigerant miscible in the oil and the oil entraining the refrigerant, upon compressor shut down, accumulates in the sump but does not reach the intermeshed rotors and thus prevents clutch burnout by liquid locking during initiation of compressor operation with the clutch mechanically connecting the engine to the intermeshed helical screw rotors.

公开(公告)号：US4439121A

公开(公告)日：1984-03-27

申请号：US354008

申请日：1982-03-02

申请人： David N. Shaw

发明人： David N. Shaw

IPC分类号： F04C18/16 ,  F04C29/02

CPC分类号： F04C29/02

摘要： Intermeshed helical screw rotors are mounted for rotation by anti-friction bearings surrounding integral shafts extending axially outward of the ends of the intermeshed screw rotors and within respective high pressure outlet and low pressure inlet bearing housings, sealed to the exterior. Oil from a separator/sump at or near compressor discharge pressure feeds via a closed passage to annular cavities surrounding the rotor shafts upstream of the outlet housing bearings. Oil seeps through very narrow annular gaps functioning as self-cleaning upstream capillaries to the outlet bearing cavities with the pressure reduction causing oil mist lubrication of the confined bearings within the outlet bearing housing. Further passages fluid connect the outlet bearing housing cavities to similar cavities within the inlet bearing housing where mist lubrication of the inlet bearings occurs. Further, oil passage means connect the inlet bearing housing cavities to an oil injection port via a downstream capillary with the oil injection port opening to the working chamber first closed thread. The upstream and downstream capillaries insure proper pressure reduction through the single loop lubrication system and the downstream capillary functions to maintain a pressure differential between the inlet bearing housing and the suction side of the intermeshed screws when the slide valve shifts to full unloaded position such that the oil injection port is open directly to the suction port of the compressor.

摘要翻译： 相互啮合的螺旋螺旋转子通过围绕从相互啮合的螺杆转子的端部轴向向外延伸的整体轴以及密封到外部的相应的高压出口和低压入口轴承壳体内的抗摩擦轴承安装。 在压缩机出口压力处或其附近的分离器/贮槽的油通过封闭通道供给到围绕出口壳体轴承的转子轴的环形空腔。 油渗透非常狭窄的环形间隙，作为自清洁上游毛细管到出口轴承腔，减压导致出口轴承壳体内的受限轴承的油雾润滑。 另外的通道将出口轴承壳体空腔连接到入口轴承壳体内类似的空腔，其中进口轴承发生雾化润滑。 此外，油通道装置通过下游毛细管将入口轴承座腔连接到注油口，其中注油口通向工作室第一闭合螺纹。 上游和下游毛细管通过单回路润滑系统和下游毛细管功能确保适当的压力降低，以在滑阀转换到完全卸载位置时保持入口轴承壳体和啮合螺钉的吸力侧之间的压力差，使得 注油口直接打开到压缩机的吸入口。

公开(公告)号：US4412788A

公开(公告)日：1983-11-01

申请号：US255410

申请日：1981-04-20

申请人： David N. Shaw ,  David J. First

发明人： David N. Shaw ,  David J. First

IPC分类号： F04B49/02 ,  F04C28/12

CPC分类号： F04C28/125

摘要： An electronic control system for sequential actuation of a four-way solenoid valve is used to selectively load and unload a slide valve control for a screw compressor. The electronic control system can be responsive to output or refrigerant pressure or evaporator pressure or inlet pressure and pulses a four-way solenoid valve to selectively load and unload the compressor so that it will maintain system pressure within a preselected deadband. Selective pulsing of the four-way solenoid valve is used to gate hydraulic fluid to load and unload chambers separated by a piston coupled to a slide valve which shifts longitudinally and changes the capacity of the screw compressor. The control system senses system pressure (reflecting load), and when a limit pressure is reached, a gas bypass solenoid valve (or dump valve) and fast-unload system is actuated to entirely unload the compressor. The control circuit also monitors current to the motor which drives the screw compressor. When the motor current is above a normal limit, further loading of the compressor is inhibited. If the current continues to rise, indicating a decrease in voltage available for power, the compressor is driven to an unloaded state until the current matches the preset normal limits. By use of electronic control for selective pulsing of the four-way solenoid valve, energy savings are realized by maintaining operation within a narrow deadband of operation.

摘要翻译： 用于顺序驱动四通电磁阀的电子控制系统用于选择性地加载和卸载用于螺杆式压缩机的滑阀控制。 电子控制系统可以响应于输出或制冷剂压力或蒸发器压力或入口压力，并且脉冲四通电磁阀来选择性地加载和卸载压缩机，使得其将系统压力保持在预选的死区内。 四通电磁阀的选择性脉冲用于对液压流体进行加载和卸载由连接到滑阀上的活塞分开的室，该活塞纵向移动并改变螺杆式压缩机的容量。 控制系统感测系统压力（反射负载），当达到极限压力时，气动旁路电磁阀（或卸载阀）和快速卸载系统被启动，以完全卸载压缩机。 控制电路还监控驱动螺杆式压缩机的马达的电流。 当电动机电流高于正常极限时，抑制压缩机的进一步负载。 如果电流继续上升，表示电力可用电压降低，则压缩机被驱动到无负载状态，直到电流与预设的正常极限相匹配。 通过使用用于四通电磁阀的选择性脉冲的电子控制，通过将操作保持在狭窄的操作范围内来实现节能。

公开(公告)号：US4388048A

公开(公告)日：1983-06-14

申请号：US242100

申请日：1981-03-10

申请人： David N. Shaw ,  Joseph A. L. N. Gagnon

发明人： David N. Shaw ,  Joseph A. L. N. Gagnon

IPC分类号： F04C28/26 ,  F01C1/16 ,  F04B49/00 ,  F04C18/00 ,  F04C18/16 ,  F04C28/12

CPC分类号： F04C28/125

摘要： A stepping piston is projected into the path of a slide valve drive piston to limit piston movement and thus the slide valve towards maximum unload position determined by piston bottoming out against the cylinder wall. The slide valve main drive piston stroke is also correlated to desired slide valve positions along the intermeshed helical screw rotors of the helical screw rotary compressor to provide, for example, stepped unloading at compressor full load, two-thirds full load, and one-third full load.

摘要翻译： 步进活塞突出到滑阀驱动活塞的路径中，以限制活塞运动，从而将滑阀朝向最大卸载位置，由活塞向底部抵靠气缸壁确定。 滑阀主驱动活塞行程还与沿螺旋式螺杆式旋转式压缩机的相互啮合的螺旋螺旋转子的期望的滑阀位置相关联，以提供例如在压缩机满载，三分之二满载下的逐步卸载和三分之一满载 满载。

公开(公告)号：US4335582A

公开(公告)日：1982-06-22

申请号：US236372

申请日：1981-02-20

申请人： David N. Shaw ,  Norman A. L. N. Gagnon

发明人： David N. Shaw ,  Norman A. L. N. Gagnon

IPC分类号： F04C28/26 ,  F04C18/16 ,  F04C28/06 ,  F25B1/047 ,  F04B49/00

CPC分类号： F04C28/06 ,  F25B1/047 ,  F25B2600/0261

摘要： A check valve within a closed loop refrigeration system isolates the evaporator from the helical screw compressor. A normally open, solenoid operated valve is positioned within an unload line having one end coupled to a drive cylinder outboard chamber to the side of the piston opposite an inboard chamber which opens to compressor discharge pressure. The other end of the unload line is connected to the system low pressure side, downstream of the check valve. The same drive cylinder outboard chamber opens via a load line to the system high pressure side through a normally closed solenoid operated valve. Upon compressor shut down, the outboard chamber is vented to the system low pressure side, while the opposite side of the unloader drive cylinder piston sees the compressor high side, thus driving the slide valve to full unload position and eliminating the coil spring normally needed to drive the slide valve to that position.

摘要翻译： 闭环制冷系统内的止回阀将蒸发器与螺旋式螺杆式压缩机隔离开。 常开的电磁操作阀定位在卸载管线内，其一端与驱动汽缸外侧室相连接，与活塞相反侧的活塞侧相接，压缩机排出压力开启。 卸载线的另一端连接到系统低压侧，止回阀的下游。 相同的驱动缸外侧室通过一个常闭电磁阀通过负载线打开到系统高压侧。 在压缩机关闭时，外侧室被排放到系统低压侧，而卸载器驱动气缸活塞的相对侧看到压缩机高侧，从而将滑阀驱动到完全卸载位置，并消除通常需要的螺旋弹簧 将滑阀驱动到该位置。

公开(公告)号：US4257795A

公开(公告)日：1981-03-24

申请号：US893863

申请日：1978-04-06

申请人： David N. Shaw

发明人： David N. Shaw

IPC分类号： F25B1/047 ,  F25B30/02 ,  F25B47/00 ,  F25B49/02 ,  F25D21/00 ,  F25B1/00 ,  F25B41/00

CPC分类号： F25B49/022 ,  F25B1/047 ,  F25B30/02 ,  F25B47/006 ,  F25B2500/07 ,  F25B2600/026

摘要： An air source heat pump system incorporating a refrigerant charged bulb within the air flow passing over the outdoor coil of the heat pump system to sense outside ambient air temperature. The refrigerant charged bulb supplies a variable saturated pressure which acts upon a bellows of a control unit whose opposite side is subjected via a second bellows to saturated suction pressure (corresponding to refrigerant evaporating temperature) of the refrigerant returning from the outdoor coil to the inlet of the compressor. The bellows provides a spring load. An electrical switching device responsive to this pressure differential acts to first block unnecessary loading of the compressor and secondly to initiate unloading of the compressor. Additional switching means prevents excessive unloading of the compressor and insures subsequent initiation of loading to prevent liquid logging of the evaporator coil.

摘要翻译： 一种空气源热泵系统，其包括在通过热泵系统的室外线圈的空气流中的制冷剂充电灯泡，以感测外部环境空气温度。 制冷剂充电灯泡提供可变的饱和压力，该饱和压力作用在控制单元的波纹管上，控制单元的相对侧通过第二波纹管经受从室外线圈返回到制冷剂回流的制冷剂的饱和吸入压力（对应于制冷剂蒸发温度） 压缩机。 波纹管提供弹簧负载。 响应于该压力差的电气开关装置用于首先阻止压缩机的不必要的负载，其次用于启动压缩机的卸载。 额外的开关装置防止压缩机的过度卸载并且确保随后开始加载以防止蒸发器盘管的液体测井。