JPH0558832U - Variable capacity water pump - Google Patents

Abstract

(57) [Summary] [Purpose] By directly detecting the temperature of the cooling fluid and opening and closing the control valve in the fluid coupling, it is possible to obtain a reasonable circulation rate of the cooling fluid that matches the operating conditions of the engine. Providing a variable displacement water pump that can be controlled at any time. A temperature-sensitive member 10 attached to the shaft end of a pump drive shaft 3 and operating by detecting a coolant temperature; a push rod incorporated in the pump drive shaft 3 and axially operated by the temperature-sensitive member 10; A control valve 19 which is disposed in the fluid coupling 14 provided in association with the other end of the pump drive shaft 3 and which is opened and closed via the push rod and is capable of controlling the supply of the working fluid in the fluid coupling 14. Variable capacity water pump equipped.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a variable displacement water pump, and more specifically, is suitable for circulating a cooling liquid of an internal combustion engine, and the rotation speed of an impeller is controlled in response to the liquid temperature to appropriately increase or decrease the circulation amount. And a variable capacity water pump.

[0002]

[Prior Art]

 As a conventional variable displacement water pump, for example, there is one disclosed in Japanese Utility Model Publication No. 2-38022. In this type, a highly sensitive temperature sensitive member is installed outside the housing of the fluid coupling provided between the pump drive pulley and the pump shaft, and this temperature sensitive member detects the temperature of the air passing through the radiator. In addition, the temperature sensitive member is used to open and close the control valve in the fluid coupling to change the amount of viscous fluid in the working chamber. The number of rotations of the impeller is changed.

[0003]

[Problems to be solved by the device]

 However, in the above-mentioned conventional example, since the temperature sensitive member is configured to guide the air passing through the radiator and detect the temperature, there is a delay in the response to the rise or fall of the coolant temperature. However, there is a problem that the function of promptly changing the circulation amount of the cooling liquid is not fully exerted.

The object of the present invention is to pay attention to such a conventional problem, and in order to solve the problem, by directly detecting the temperature of the cooling liquid guided to the pump, the control valve in the fluid coupling is opened and closed. It is an object of the present invention to provide a variable capacity water pump capable of effectively controlling the circulation amount of the cooling liquid according to the operating state of the engine.

[0005]

[Means for Solving the Problems]

 In order to achieve such an object, the present invention relates to a temperature-sensing member disposed at an end of a pump drive shaft on a side where an impeller is mounted, in contact with a coolant passage, and a temperature-sensing member incorporated in the pump drive shaft. And a push rod that is axially operated by a return spring and is held in a pre-operation state by a return spring, and is axially fixed to the other end of the pump drive shaft extending from the pump housing, and A wheel that is rotatably held for torque transmission, a pulley that is concentrically connected to the casing of the fluid coupling and that transmits torque to the casing, and a working chamber side of the wheel that is involved in the torque transmission inside the casing. A control valve that is opened by the operation of the push rod by the temperature sensing member and that supplies the working fluid from the storage chamber to the working chamber. At high temperature Only the temperature-sensitive member opens the control valve through the push rod, and the rotational torque from the pulley is transmitted to the pump drive shaft through the wheel. Is.

[0006]

[Action]

 According to the present invention, the temperature sensitive member does not operate in an operating state in which the temperature of the coolant circulating through the engine is sufficiently low, and therefore the control valve provided in the fluid coupling is kept closed. , The working fluid is not supplied to the wheel side, and torque is hardly transmitted from the pulley to the wheel through the housing of the fluid coupling, but the impeller rotates at a low speed with the operating oil remaining in the working chamber of the fluid coupling. However, the cooling water is gently circulated and the temperature of the cooling liquid is warmed to suit the operating conditions of the engine. When the temperature of the cooling liquid rises, the temperature-sensing member operates, the control valve is opened via the push rod, and the working liquid is supplied to the working chamber side. And is forcedly circulated by the cooling liquid to efficiently cool the engine.

[0007]

【Example】

 Embodiments of the present invention will be specifically described below with reference to the drawings.

1 and 2 show an embodiment of the present invention. FIG. 1 shows a water pump for operating an engine, in which the cooling liquid has a relatively low temperature and the circulation amount of the cooling liquid does not need to be very large. FIG. 2 shows the state of the water pump when the coolant is at a relatively high temperature and it is necessary to circulate the coolant sufficiently.

Therefore, first, the configuration will be described with reference to FIG.

Here, 1 is an engine block, 2 is a pump housing fixed to the engine block 1, 3 is a pump drive shaft rotatably supported by a pump housing 2 via a ball bearing 4, and 5 is a pump drive shaft. An impeller (hereinafter referred to as a rotor) 6 attached to the shaft 3 is a mechanical seal that seals the pump chamber 7 from the ball bearing 4 side. In this example, a stepped through hole 8 having a small diameter portion 8A and a large diameter portion 8B is provided in the pump drive shaft 3, and a temperature sensitive member (for example, wax (A form in which the extruded pins are extruded by melting the wax) 10 is screwed in a liquid-tight manner. Further, 11 is a push rod slidably fitted in the through hole 8, and 12 is a spring biasing the push rod 11 toward the push pin 10A of the temperature sensitive member 10. Thus, the cooling liquid guided from the suction port 9 side to the pump chamber 7 in the direction of the arrow is guided to the discharge port 13 by the centrifugal force received from the rotor 5, and circulates to a radiator (not shown) and cooling parts in the machine. Is done.

Further, in FIG. 1, 14 is a fluid coupling provided at an outer end of the pump drive shaft 3, 14 A is a body thereof, 14 B is a cover thereof, 15 is a shaft fixed to the pump drive shaft 3, and 15 is a fluid coupling. It is a wheel that rotates in 14 and is involved in the rotation control of the pump drive shaft 3. The body 14A of the fluid coupling 14 is concentrically coupled to the pulley 16, and the rotational force is supplied from the engine side to the body 14A, which is the housing of the fluid coupling 14, and the cover 14B via the pulley 16. Reference numeral 17 is a bearing that rotatably supports the body 14A around the pump drive shaft 3, and 18 is a bearing that supports the pulley 16 on the pump housing 2.

Further, 19 is composed of a partition plate 20 having communication holes 20A and 20B, and a leaf spring-like valve lid 21 having one end fixed to the partition plate 20 and keeping the communication hole 20B closed at the other end. It is a control valve. The control valve 19 keeps the storage chamber 22 in which the viscous working fluid is stored and the working chamber 23 isolated from each other when the cooling liquid has a low temperature as shown in FIG. The working chamber 23 is formed so as to straddle both sides of the wheel 15 via a communication hole 15A provided in the wheel 15. Reference numeral 24 is an operating portion for changing the relative rotation speed between the wheel 15 and the casing of the fluid joint 14 via the viscous working fluid interposed therebetween, and 25 is provided on the cover 14B side of the fluid coupling 14. A return passage for returning the viscous working fluid on the side of the operation chamber 23 to the side of the storage chamber 22.

Next, the control operation for changing the circulation amount of the cooling liquid by the variable displacement water pump configured as described above will be described.

Now, when the temperature of the cooling liquid is low, that is, when the engine is in the initial stage of starting or when the engine is operating at low rotation and low load, the wax inside the temperature-sensitive member 10 remains solidified and contracted, and the extrusion pin 10A On the other hand, the push rod 11 is not projected, but is pulled back in the direction of arrow A along the small diameter portion 8A by the elastic force of the spring 12, and is maintained in the state shown in FIG. Therefore, the control valve 19 keeps the communication hole 20B closed due to the spring property of the valve lid 21, and the working oil is not supplied from the storage chamber 22 side to the working chamber 23 side, and remains in the operating portion 24 by that time. The wheel 15 transmits the rotation from the pulley 16 to the pump drive shaft 3 in a form in which the rotation from the pulley 16 is extremely slowed only by the resistance of the working fluid. Therefore, the cooling liquid circulated by the low speed rotation of the impeller 5 is also suppressed to a minimum.

Next, when the temperature of the cooling liquid rises due to a high load or high speed rotation of the engine, the wax melts and expands in the temperature sensitive member 10, and the extrusion pin 10A projects. Then, the push-out rod 11 is moved leftward against the spring force of the spring 12 by the protrusion of the push-out pin 10A as shown by arrow B in FIG. To open the communication hole 20B. Therefore, the working fluid is supplied from the storage chamber 22 to the working chamber 23, and sufficient torque is transmitted from the pulley 16 to the wheel 15 through the housing of the fluid coupling 14 due to the sufficient viscosity of the working fluid. Thus, the impeller 5 rotates at a high speed by the rotation of the pump drive shaft 3, and the circulation amount of the cooling liquid can be increased by the rotation substantially corresponding to the rotation speed of the engine.

Here, the working fluid is returned from the working chamber 23 to the storage chamber 22 via the return passage 25 provided in the cover 14B by the centrifugal force generated by the rotation of the wheel 15, and is circulated therein. Will always be supplied with sufficient working fluid. Further, here, by configuring the fluid coupling actuating portion 24 in a labyrinth configuration, it is possible to transmit higher torque.

[0017]

[Effect of the device]

 As described above, according to the present invention, the temperature-sensing member disposed in contact with the cooling liquid passage at the end of the pump drive shaft on which the impeller is mounted, and the temperature-sensing member incorporated in the pump drive shaft are used. Inside the housing of the fluid coupling, the push rod is axially operated by the warm member and is held in the pre-operation state by the return spring, and is axially fixed to the other end of the pump drive shaft extending from the pump housing. A wheel involved in torque transmission, which is rotatably held in the housing, a pulley which is concentrically connected to the casing of the fluid coupling and transmits torque to the casing, and a wheel which is involved in the torque transmission in the casing. A cooling valve, which is isolated from the working chamber side and the working fluid storage chamber, is opened by the operation of the push rod by the temperature sensing member, and supplies the working fluid from the storage chamber to the working chamber; High temperature of liquid The control valve is opened by the temperature sensing member via the push rod only, and the rotational torque from the pulley is transmitted to the pump drive shaft via the wheel, so that a low load or starting When the temperature of the equal cooling liquid is low, the control valve 19 is closed in the fluid coupling, and the hydraulic liquid is mostly returned to the storage chamber 22 via the return passage 25. Therefore, the torque transmitted from the pulley 16 to the pump drive shaft 3 via the wheel 15 is small, and the warming up of the engine is promoted by slowing the delivery of the coolant, which contributes to the improvement of fuel efficiency. Further, even during normal running, the temperature-sensing member 10 does not operate when the temperature of the cooling liquid is not so high, and therefore, the torque is not transmitted in the fluid coupling 14 so much that the water pump hardly operates. It is possible to reduce the horsepower consumption. Then, when the operating condition is such that the engine needs to be cooled by the circulation of the cooling liquid, the control valve 19 is operated by the temperature sensitive member due to the temperature rise of the cooling liquid, and the torque is pumped through the fluid coupling 14. It can be transmitted to the shaft 3 and sufficient cooling liquid can be circulated by the pump.

[Brief description of drawings]

FIG. 1 is a sectional view showing the structure of a variable displacement water pump according to the present invention in a low temperature state of a cooling liquid.

FIG. 2 is a cross-sectional view showing the configuration of the variable displacement water pump of the present invention in a high temperature state of the cooling liquid and an operating state of the fluid coupling.

[Explanation of symbols]

 1 Engine Block 2 Pump Housing 3 Pump Drive Shaft 4, 17, 18 Ball Bearing 5 Impeller (Rotor) 6 Mechanical Seal 9 Suction Port 10 Temperature Sensitive Member 11 Push Rod 12 Spring 13 Discharge Port 14 Fluid Joint 15 Wheel 15A Communication Hole 16 Pulley 19 Control valve 20 Partition plates 20A, 20B Communication hole 21 Valve lid 22 Storage chamber 23 Working chamber 24 Working part

Claims (1)

[Scope of utility model registration request] 1. A temperature-sensing member disposed at an end of a pump drive shaft on the side of an impeller mounting side in contact with a cooling liquid passage, and incorporated in the pump drive shaft so as to be axially operated by the temperature-sensing member. A push rod that is held in a pre-operation state by a return spring, and a torque transmission that is rotatably held in the housing of the fluid coupling by being axially locked to the other end of the pump drive shaft extending from the pump housing. And a pulley that is concentrically connected to the housing of the fluid coupling and that transmits torque to the housing, and that isolates the inside of the housing between the working chamber side of the wheel that is involved in the torque transmission and the working fluid storage chamber. And a control valve that is opened by the operation of the push rod by the temperature sensitive member and that supplies the working fluid from the storage chamber to the working chamber, wherein the temperature sensitive member is used only when the temperature of the coolant is high. Wherein the control valve is opened via the rod, variable displacement water pump rotational torque from said pulley to the pump drive shaft through the wheel, characterized in that it has to be transmitted.