Patent Description:
Lubricating oil should be accommodated in a transmission of a vehicle, which can perform functions of lubrication and cooling, and the lubricating oil is required to be controlled at an appropriate working temperature.

When the temperature of the lubricating oil in the transmission is high, it can be cooled by an external cooling device. The cooling device includes a heat exchanger, which uses cooling water or refrigerant to cool the lubricating oil with a higher temperature, so as to achieve the purpose of keeping the lubricating oil of the transmission within a certain working temperature range. When the temperature of the lubricating oil is low, the lubricating oil does not pass through the cooling device, that is, when the lubricating oil of the transmission flows out, there are two flow paths, one flow path is through the cooling device, and the other is not through the cooling device.

At present, the switching of the above two flow paths is performed through a thermostatic valve. The thermostatic valve is provided with a thermal actuator and a spring. The thermal actuator thermally expands and contracts according to the temperature of the fluid sensed by the thermosensitive substance. During the thermal expansion, a force is transmitted to the spring, the flow path through the cooling device is opened; and during the cold contraction, the spring is reset, and the flow path through the cooling device is bypassed.

However, the above solution has the following technical problems.

There is a certain response time required from sensing temperature by the thermosensitive substance to the thermal expansion and contraction process then to applying the force on the spring, that is, the response time of the thermal actuator is long, which will cause a certain hysteresis of the temperature of the lubricating oil, and then affect the performance of the transmission. In addition, the thermal actuator including the above thermosensitive substance has a large volume.

Alternative thermostatic valves are disclosed in <CIT> or <CIT>.

A thermostatic valve is provided according to the present application, to improve the sensing time of the temperature control.

A thermostatic valve is provided according to claim <NUM>.

Compared with the technical solution with the thermal actuator, the response time of the solution using the memory spring is faster and the first valve port can be opened in time to switch the medium to another flow path in the above technical solution. When being applied to coolers and transmissions, it can improve the performance of the transmission. Moreover, compared with the thermal actuator, the combination of the memory spring and the valve core is lighter in weight and smaller in volume.

In order to make those skilled in the art to better understand the technical solutions of the present application, the present application is further described in detail below in conjunction with the drawings and specific embodiments.

Referring to <FIG>, <FIG> is a schematic view showing the structure of a thermostatic valve according to a first embodiment of the present application; <FIG> is a schematic view of the thermostatic valve in <FIG> viewed at another angle, showing the bottom; <FIG> is a sectional view of the thermostatic valve in <FIG>, with a second valve port closed and a first valve port opened; <FIG> is a schematic view of the thermostatic valve in <FIG> after a valve core is moved to the right, with the first valve port closed and the second valve port opened; and <FIG> is a schematic view of a valve body in <FIG>.

The thermostatic valve according to the first embodiment includes a valve body <NUM>, and a valve cavity 10a is formed inside the valve body. Specifically, in this embodiment, as shown in <FIG> and <FIG>, the valve cavity 10a penetrates one end surface of the valve body <NUM> from left to right, to form the valve cavity 10a with an end port at the left end, and an end cover <NUM> is used to block the end port. A valve core <NUM> is provided in the valve cavity 10a, and the valve core <NUM> can move axially along the valve cavity 10a. The axial direction here refers to an extending direction of the valve cavity 10a from one end to the other end, which is the left-right direction shown in <FIG>. When the valve body <NUM> is in the rectangular parallelepiped shape as shown in <FIG>, the axial direction here also refers to the length direction of the valve body <NUM> or the length direction of the valve cavity 10a.

The thermostatic valve has a first outlet <NUM>, a second inlet <NUM> and a second outlet <NUM>, and also has a first inlet <NUM> in communication with the valve cavity 10a. In this embodiment, the above inlets and outlets are integrally formed in an outer wall of the valve body <NUM>, which can be connected to external members. In <FIG>, a first valve port B for communicating the valve cavity 10a with the second outlet <NUM> and a second valve port A for communicating the valve cavity 10a with the first outlet <NUM> are also provided in the valve body <NUM>. The second valve port A is specifically provided in a side cavity wall of the valve cavity 10a, and an outlet passage 10d is formed between the second valve port A and the first outlet <NUM>. The first valve port B is formed in an end cavity wall of the valve cavity 10a, that is, the cavity wall at the right end in <FIG>, and the left end is the end port blocked by the end cover <NUM>. The first valve port B is in communication with the second outlet <NUM> through the second outlet passage, and the second outlet passage in <FIG> includes a small hole 10c, and a linear passage 10b between the second inlet <NUM> and the second outlet <NUM>.

The thermostatic valve according to all the embodiments herein can be used between a transmission and a cooler. The medium flowing inside the thermostatic valve is lubricating oil. That is, the first outlet <NUM> of the thermostatic valve is in communication with an inlet of the cooler, the second inlet <NUM> is in communication with an outlet of the cooler, the second outlet <NUM> is in communication with an inlet of the transmission, and the first inlet <NUM> is in communication with an outlet of the transmission. After flowing out of the transmission, the lubricating oil enters the thermostatic valve through the first inlet <NUM>, and then the lubricating oil flows directly back to the transmission through the first port B and the second outlet <NUM>, or the lubricating oil enters the cooler through the second port A and the first outlet <NUM> to be cooled, and returns to the transmission through the second inlet <NUM> and the second outlet <NUM>. The following main working process is also exemplified by this application. However, it can be understood that the transmission and the cooler are only a typical application of the thermostatic valve in the present application. Obviously, besides the transmission, the thermostatic valve can also be applied to other applications that are required to control temperature to adjust the medium flow path.

Specifically, the valve core <NUM> in this embodiment is movable to switch the opening and closing of the first valve port B and the second valve port A. As shown in <FIG>, the valve core <NUM> can move right to block the first valve port B and open the second valve port A; and the valve core <NUM> can move left to block the second valve port A and open the first valve port B. The opening and closing of the first valve port B and the second valve port A realize the switching of the two flow paths; and when the thermostatic valve is applied to the transmission and the cooler, the lubricating oil can be cooled by passing through the cooler or can directly return to the transmission without cooling.

The movement of the valve core <NUM> is mainly achieved by a return spring <NUM> and a memory spring <NUM> provided in the valve cavity 10a. The memory spring <NUM> is a spring made of a shape memory alloy material (SMA: Shape Memory Alloy). The return spring <NUM> can provide a return force that causes the valve core <NUM> to open the first valve port B. In this embodiment, the return spring <NUM> is a tension spring, that is, it provides a pulling force. The direction of the pulling force of the valve core <NUM> in <FIG> is leftward. The leftward spring can play the role of connecting the valve core <NUM>. The valve core <NUM> can be processed into a structure with an I-shaped axial cross section as shown in the figure, to reduce weight and facilitate movement. When the temperature rises to a specified value, the elastic characteristic of the memory spring <NUM> is activated, and the memory spring <NUM> has an elastic potential energy to provide the elastic force. The direction of the elastic force is opposite to the direction of the pulling force to drive the valve core <NUM> to move against the return force. The specified value corresponding to the elasticity of the memory spring <NUM> being activated can be determined by selecting materials according to the requirement, so that the memory spring <NUM> can be deformed due to increased temperature at the ambient temperature where the path switching is required.

The following working principle of this embodiment is described as follows.

In the working state shown in <FIG>, the medium (for example, the above lubricating oil of the transmission) flows from the first inlet <NUM> into the valve cavity 10a of the thermostatic valve. Since the second valve port A is closed and the first valve port B is opened, the medium flows to the small hole 10c, the linear passage 10b, and the second outlet <NUM> through the first valve port B, and returns to the transmission.

When the medium temperature rises to a specified value, the thermostatic valve is in the working state shown in <FIG>, the elastic characteristic of the memory spring <NUM> is activated, and the elastic force generated is greater than the return force of the return spring <NUM>. At this time, the valve core <NUM> moves toward the first valve port B under a difference between forces applied by the memory spring <NUM> and the return spring <NUM>. The valve core <NUM> can block the first valve port B and open the second valve port A. After the medium flows in from the first inlet <NUM>, the medium enters the cooler through the second valve port A, the outlet passage 10d, and the first outlet <NUM>, to be cooled. The cooled lubricating oil flows out of the cooler, and then enters the valve cavity 10a from the second inlet <NUM>, and re-enters the transmission through the linear passage 10b and the second outlet <NUM>.

After the temperature of the medium drops below a specified value, the elastic characteristic of the memory spring <NUM> fails, the elastic force decreases and then disappears, and the valve core <NUM> moves away from the first valve port B under the return force of the return spring <NUM>, and at this time, the first valve port B is opened, the second valve port A is closed and the valve core <NUM> returns to the state shown in <FIG>. It can be seen that the memory spring <NUM> according to this embodiment serves as a thermal actuator that drives the action of the valve core <NUM>, and the structure is simple.

In this embodiment, the memory spring <NUM> and the return spring <NUM> are both provided between the end cover <NUM> and the valve core <NUM>. Obviously, the arrangement manner is not limited to this.

Referring to <FIG>, <FIG> is a sectional view showing the structure of a thermostatic valve according to a second embodiment of the present application, with the second valve port A closed and the first valve port B opened; and <FIG> is a schematic view of the thermostatic valve in <FIG> after the valve core is moved to the right, with the first valve port B closed and the second valve port A opened.

This embodiment is basically the same as the first embodiment. The memory spring <NUM> is located between the end cover <NUM> and the valve core <NUM>. The memory spring <NUM> has one end in contact with another end of the valve core <NUM>, and another end in contact with the end cover <NUM>. A stepped hole is formed in the valve body <NUM>, and the large hole of the stepped hole is the valve cavity 10a, and the first valve port B is formed at a junction of the small hole 10c and the large hole. The difference is that, in this embodiment, the return spring <NUM> in <FIG> provides a resilience force instead of a pulling force, that is, the return spring <NUM> and the memory spring <NUM> can be respectively provided at two ends of the valve core <NUM>. One end of the return spring <NUM> is in contact with one end of the valve core <NUM>, and the other end of the return spring <NUM> abuts against the valve body <NUM> to provide the valve core <NUM> with a force in the opposite direction.

Specifically, the return spring <NUM> is provided in the small hole 10c, and a step is provided in the small hole 10c. The return spring <NUM> is pre-compressed between the valve core <NUM> and the step, to provide the resilience force for driving the valve core <NUM> away from the first valve port B, and the direction of the resilience force is opposite to the direction of the elastic force of the memory spring <NUM> applied on the valve core <NUM>. At this time, the right end, facing the return spring <NUM>, of the valve core <NUM> may be provided with a protrusion to be inserted into the return spring <NUM>, to assemble the return spring <NUM> and also play a role of positioning and guiding the valve core <NUM>.

Of course, the step may not be provided in the small hole 10c, and the right end of the return spring <NUM> may directly abut against the inner wall of the linear passage 10b, or a recessed hole is provided in the inner wall of the linear passage 10b, and the right end of the return spring <NUM> directly abuts against the recessed hole. The return spring <NUM> can also be pre-compressed between the valve core <NUM> and the cavity wall of the right end portion of the valve cavity 10a.

In addition, in the first and second embodiments, the right end of the valve core <NUM> is its sealing portion, which can block the first valve port B when the valve core <NUM> moves to the right; and the memory spring <NUM> serves as the sealing portion of the second valve port A. When the temperature of the medium is low, the memory spring <NUM> is in a compressed and tight state and in correspondence to the position of the second valve port A, to block the second valve port A. When the memory spring <NUM> is heated up and expands, the memory spring <NUM> deforms and stretches, the diameter of the memory spring <NUM> decreases, and a gap appears between the second valve port A and the memory spring <NUM>, and a notch may also appear between several spring coils of the memory spring <NUM>, and the medium in the valve cavity 10a may flow through the gap and the notch to the second valve port A and then flow out. At this time, the second valve port A is opened. It can be seen that, with this arrangement, the memory spring <NUM> not only serves as a thermal actuator that drives the movement of the valve core <NUM>, but also serves as a sealing portion, thereby simplifying the structure of the valve core <NUM>.

Of course, the manner of blocking the second valve port A is not limited to that. Referring to <FIG>, <FIG> is a sectional view showing the structure of a thermostatic valve in an initial state according to a third example not according to the claims, with a first valve port B having a preset opening degree and a second valve port A having a preset opening degree; <FIG> is a schematic view of the thermostatic valve in <FIG> after the temperature rises to a specified value and the memory spring <NUM> is deformed, with the first valve port B closed and the second valve port A opened; <FIG> is a schematic view of the thermostatic valve in <FIG> after the temperature drops below a specified value and the memory spring <NUM> loses characteristics, with the first valve port B opened and the second valve port A closed; and <FIG> is a schematic view showing the structure of the valve core <NUM> in <FIG>.

In this example, the second valve port A is also provided in the side cavity wall of the valve cavity 10a, and the first valve port B is provided in the end cavity wall of the valve cavity 10a. In comparison, the valve core <NUM> in this example is additionally provided with a sleeve portion <NUM>, and the memory spring <NUM> is provided in the sleeve portion <NUM> and located between the end cover <NUM> and the valve core <NUM>. At this time, the right end of the valve core <NUM> forms a first sealing portion for blocking the first valve port B, and the sleeve portion <NUM> on the valve core <NUM> forms a second sealing portion for blocking the second valve port A. Specifically, the outer wall of the sleeve portion <NUM> can slide along the side cavity wall of the valve cavity 10a, to block or open the second valve port A. At this time, the memory spring <NUM> only serves as a thermal actuator that drives the valve core <NUM> to move according to temperature changes.

To facilitate the assembly of the memory spring <NUM>, a protruding platform is provided on the inner end surface of the end cover <NUM> facing the valve core <NUM>, and one end of the memory spring <NUM> is sleeved on the protruding platform. The valve core <NUM> includes a main body portion <NUM> extending in the axial direction and a sleeve portion <NUM> sleeved outside a part of the main body portion <NUM>. The left end of the main body portion <NUM> extends into the sleeve portion <NUM>. Another end of the memory spring <NUM> is sleeved on the left end of the main body portion <NUM>. The sleeve portion <NUM> and the main body portion <NUM> of the valve core <NUM> may be separately processed or integrally formed, as shown in <FIG>.

In the third example, same as the first and second embodiments, a stepped hole is also formed in the valve body <NUM>. The large hole of the stepped hole is the valve cavity 10a, and the first valve port B is formed at the junction of the large hole of the stepped hole and the small hole 10c. In addition, the right end of the main body portion <NUM> of the valve core <NUM> serves as a first sealing portion and is also connected to a guide rod <NUM>. The guide rod <NUM> and the main body portion <NUM> may be individually formed or integrally formed. The guide rod <NUM> can be inserted into the small hole 10c to guide the movement of the valve core <NUM>. The feature that the guide rod <NUM> is provided on the valve core <NUM> to be inserted into the small hole 10c for guiding is also applicable to other embodiments. As shown in <FIG>, the end of the valve core <NUM> facing the first valve port B may be hollow, to reduce weight and save material.

In the second embodiment, as a sealing portion for sealing the first valve port B, the right end of the valve core <NUM> is provided with a protruding platform to be inserted into the return spring <NUM>. The return spring <NUM> is located in the small hole 10c, and can also play a certain guiding role; however, in the third example, the guide rod <NUM> is directly inserted into the small hole 10c for guiding, and the guiding effect is better. Since the sleeve portion <NUM> is provided, the step is not required to be processed on the hole wall of the small hole 10c to install the return spring <NUM>. The return spring <NUM> can be arrange between the sleeve portion <NUM> and the end cavity wall of the valve cavity 10a, as shown in <FIG>.

In addition, in the third example, since the valve core <NUM> is provided with the sleeve portion <NUM>, the sleeve portion <NUM> is in sliding fit with the side cavity wall of the valve cavity 10a, and an opening 402b is provided at the bottom of the sleeve portion <NUM> close to the first inlet <NUM>, as shown in <FIG> (that is, below the bottom in <FIG>), so that the medium can flow into the inner cavity of the sleeve portion <NUM> and thus flows to the second valve port A. In order to facilitate the medium to come into contact with the memory spring <NUM> faster and more, a guiding inlet 402a penetrating the bottom is further provided at the bottom of the sleeve portion <NUM> away from the first inlet <NUM> (above the bottom in <FIG>) in <FIG>, and as a flow guiding passage, the guiding inlet <NUM> is configured to communicate the valve cavity 10a with the inner cavity of the sleeve portion <NUM>. The number of the guiding inlet 402a may be one or more.

It should be noted that, in the third example, an end protruding platform 401a is provided at the left end of the main body portion <NUM> of the valve core <NUM>. In the initial state, that is when leaving factory, one end of the memory spring <NUM> is surrounded around the end protruding platform 401a, abuts against the stepped surface formed by the end protruding platform 401a and the main body portion <NUM>, which is the initial position of the end of the memory spring <NUM>. As shown in <FIG>, the first valve port B is not fully opened and has a preset opening degree, the second valve port A also has an initial preset opening degree, so that the thermostatic valve has the characteristic of the second valve port A being always open in the initial state, thereby facilitating filling the lubricating oil into the transmission and at the same time filling the lubricating oil into the cooler in the initial state, to meet the requirement of the initial filling. That is, both valve ports are opened.

After that, when the temperature of the lubricating oil rises to a specified value, the memory spring <NUM> deforms and expands to a certain extent, thereby detaching from the end protruding platform 401a and surrounding the main body portion <NUM> with a greater outer diameter. The memory spring <NUM> is then switched to a normal working state, and always surrounds the main body portion <NUM>, as shown in <FIG>, and is deformed to abut against the bottom position of the sleeve portion <NUM>. This position is the working position. At this time, the first valve port B is kept closed under the elastic force of the memory spring <NUM>. The initial position and working position of the end of the memory spring <NUM> described in the present application refer to the relative position of the end and the valve body <NUM> (the cavity wall of the valve cavity or the end cover <NUM> of the valve body <NUM>) or the relative position of the end and the valve core <NUM>, and do not change as the valve core <NUM> moves.

When the temperature is lower than a specified value, the memory spring <NUM> loses its characteristic. Under the action of the return force of the return spring <NUM>, the valve core <NUM> moves and compresses the memory spring <NUM>. The distance between the bottom of the sleeve portion <NUM> and the end cover <NUM> is greater than the distance between the protruding platform of the main body portion <NUM> and the end cover <NUM>, thus when the memory spring <NUM> detaches from the protruding platform of the main body portion <NUM> and surrounds the main body portion <NUM>, the valve core <NUM> is closer to the end cover <NUM> under the action of the return spring <NUM>, and the sleeve portion <NUM> will block the second valve port A, eliminating the initial preset opening degree, as shown in <FIG>.

It can be seen that a setting method is provided according to this example, that is, a two-stage step (a stepped surface between the end protruding platform 401a and the main body portion <NUM> is a first stepped surface, and the bottom of the sleeve portion <NUM> is a second stepped surface) is provided on the valve core <NUM>, and the initial position and the working position are respectively formed by the first stepped surface and second stepped surface. When the memory spring <NUM> is at the initial position, the first valve port B has a preset opening degree, and the distance between the valve core <NUM> and the first valve port B when the memory spring <NUM> is at the initial position is smaller than the distance between the valve core <NUM> and the first valve port B when the memory spring <NUM> is at the working position and the temperature is below a specified value.

When the valve core <NUM> is at a certain position, the distance between the initial position and the end cover <NUM> is smaller than the distance between the working position and the end cover <NUM>. In this way, when the memory spring <NUM> is in any temperature environment (not affected by the specified value), the first valve port B maintains in a closed state, and the second valve port A has a preset opening degree (if the second valve port A is not provided, the medium can flow directly to the first outlet <NUM>). After at the working position, the distance between the end cover <NUM> and the valve core <NUM> becomes longer, so that the return spring <NUM> can drive the valve core <NUM> to compress the memory spring <NUM> by more distance, thereby opening the first valve port B and closing the second valve port A.

It can be understood that the setting of the initial position and the working position is to adjust the distance between the valve core <NUM> and the end cover <NUM> or the valve core <NUM> and the valve body <NUM>, so that the distance between the two ends of the memory spring <NUM> can be compressed to different degrees at the two working positions, thereby achieving the opening and closing of the first valve port B. Therefore, the initial position and the working position can also be set at the valve core <NUM> or the valve body <NUM>, which can also be achieved by the two-stage step method, and both the valve core <NUM> and the valve body <NUM> can be set with the initial position and the working position, or both the valve core <NUM> and the end cover <NUM> can be set with the initial position and the working position, so that both ends of the memory spring <NUM> can abut against the initial position or the working position.

In the above example, the first outlet <NUM>, the second inlet <NUM>, the second outlet <NUM>, and the first inlet <NUM> are all provided in the side wall of the valve body <NUM>, the first valve port B is provided in the end cavity wall of the valve cavity 10a, and the second valve port A is provided in the side cavity wall of the valve cavity 10a. The second outlet <NUM> and the second inlet <NUM> are opposite to each other, and a linear passage 10b (a linear passage 10b is also formed in the other embodiments and examples described below) is formed between the second outlet <NUM> and the second inlet <NUM>. The first valve port B is in communication with the linear passage 10b, which is specifically in communication with the linear passage 10b through the small hole 10c of the stepped hole in the above embodiment. In this way, the first inlet <NUM> and the second inlet <NUM> can share a passage to the second outlet <NUM>, thereby simplifying the structure and facilitating processing. Of course, other setting methods can also be adopted.

The inlets, outlets, and valve ports of the thermostatic valve can also be set by other ways.

Referring to <FIG>, <FIG> is a sectional view showing the structure of a thermostatic valve in an initial state according to a forth example of the present application, with a first valve port B having a preset opening degree and a second valve port A having a preset opening degree; <FIG> is a schematic view of the thermostatic valve in <FIG> after the temperature rises to a specified value and the memory spring <NUM> is deformed, with the first valve port B closed and the second valve port A opened; <FIG> is a schematic view of the thermostatic valve in <FIG> after the temperature drops below a specified value and the memory spring <NUM> loses characteristics, with the first valve port B opened and the second valve port A closed; and <FIG> is a schematic view showing the structure of the end cover <NUM> in <FIG>.

In this example, the end cover <NUM> actually not only covers the end port position of the valve body <NUM>, but also becomes a seat switching structure to function as a connector for communicating with the outside, specifically for communicating with the cooler in this example. The switching seat is provided with a passage penetrating the inside and outside of the switching seat, and an outlet passage 10d is formed by the passage. The internal end port of the outlet passage 10d is the second valve port A, and the external end port is the first outlet <NUM>. At this time, the second valve port A and the first valve port B are distributed along the axial direction of the valve cavity 10a. In this way, during the movement of the valve core <NUM>, one end of the valve core <NUM> may be a first sealing portion for blocking the first valve port B, and the other end is a second sealing portion for blocking the second valve port A. In this way, the operation is more convenient for the valve core <NUM> to block the first valve port B and the second valve port A, and the valve core <NUM> is easier to process. In this example, in addition to the first outlet <NUM> of the thermostatic valve formed by the end cover <NUM> with the seat switching structure, the second outlet <NUM>, the second inlet <NUM>, and the first inlet <NUM> are also formed by connectors <NUM> externally connected to the valve body <NUM>. In the first embodiment to third example, the outlets and inlets in communication with the outside are each directly formed as a connector-like structure on the valve body <NUM>, and both solutions are applicable to all embodiments and examples of the present solution.

In addition, in the fourth example, the setting of the initial preset opening degree is also performed. As can be understood with reference to <FIG>, a two-stage step is provided at the inner end, toward the valve core <NUM>, of the switching seat, and the outer diameter of the first step is smaller than the outer diameter of the second step, forming a first step surface <NUM> and a second step surface <NUM> that both face the valve core <NUM>, the first step surface <NUM> is the initial position and the second step surface <NUM> is the working position. The distance between the valve core <NUM> and the initial position is smaller than the distance between the valve core <NUM> and the working position. In this way, in the initial state of leaving factory, the left end of the memory spring <NUM> is surrounded around the first step of the valve core <NUM> and abuts against the first step surface <NUM>. At this time, the first valve port B is closed and the second valve port A has the initial preset opening degree, as shown in <FIG>, so that the thermostatic valve has the characteristic of the second valve port A being always open in the initial state, thereby facilitating filling the lubricating oil into the transmission in the initial state and at the same time filling the lubricating oil into the cooler, to meet the requirement of the initial filling. Of course, when the second valve port A is not provided, the memory spring <NUM> abuts against the initial position, the first valve port B is closed, and the lubricating oil can directly flow into the cooler through the first outlet <NUM>.

After that, when the temperature of the lubricating oil rises to a specified value, the memory spring <NUM> deforms and expands to a certain extent, thereby detaching from the first step and surrounding around the second step. After that, the memory spring <NUM> is switched to the normal working position and will be always surrounded around the second step, as shown in <FIG>. The memory spring <NUM> is also deformed to abut against the second step surface <NUM>. At this time, the first valve port B is kept closed under the elastic force of the memory spring <NUM>.

When the temperature is lower than a specified value, the memory spring <NUM> loses its characteristic. Under the action of the return force of the return spring <NUM>, the valve core <NUM> moves and compresses the memory spring <NUM>. The distance between the second step surface <NUM> and the valve core <NUM> is greater than the distance between the first step surface <NUM> and the valve core <NUM>, thus when the memory spring <NUM> is detached from the first step and surrounded around the second step, the valve core <NUM> will be closer to the end cover <NUM> under the action of the return spring <NUM>, and the left end portion of the valve core <NUM> will block the second valve port A, eliminating the initial preset opening degree, and the first valve port B is now open.

In the fourth example, the outer periphery of the end (the left end portion in <FIG>, that is, the second sealing portion), facing the second valve port A, of the valve core <NUM> is tapered, that is, having a tapered surface that cooperates with the second valve port A, in order to better block the second valve port A and have a guiding effect. In order to facilitate abutting against the memory spring <NUM>, the left end portion of the valve core <NUM> is also provided with a peripheral protrusion as shown in <FIG>, the right end of the memory spring <NUM> abuts against the peripheral protrusion. The end (the right end portion in <FIG>, that is, the first sealing portion), facing the first valve port B, of the valve core <NUM> has a protruding platform and the protruding platform can be inserted into the return spring <NUM>. The return spring <NUM> is placed in the small hole 10c.

The valve core <NUM> may also have other structures, as shown in <FIG>. <FIG> is a sectional view showing the structure of a thermostatic valve in an initial state according to a fifth example of the present application, with a first valve port B having a preset opening degree and a second valve port A having a preset opening degree; and <FIG> is a schematic view of the thermostatic valve in <FIG> after the temperature rises to a specified value and the memory spring <NUM> is deformed, with the first valve port B closed and the second valve port A opened.

This example is basically same as the fourth example, and the difference lies only in the structure of the valve core <NUM>. In this example, the valve core <NUM> is a spherical body. When the spherical valve core <NUM> is used to block the first valve port B and the second valve port A, a better blocking effect can be realized. In other examples, the spherical valve core <NUM> may also be used, or at least the portion for blocking is processed into a spherical surface.

In the fifth example, a two-stage step is also provided on the end cover <NUM> with the seat switching structure, so that the memory spring <NUM> has an initial shape and forms an initial preset opening degree, which facilitates to filling the cooling oil into the cooler.

Regarding the structure of the valve core <NUM>, reference can be further made to <FIG>, which is a sectional view showing the structure of a thermostatic valve according to a sixth example of the present application, with a first valve port B closed and a second valve port A opened; and <FIG> is a schematic view showing the structure of the valve core <NUM> in <FIG>.

This example is the same as the fourth and fifth examples, except that the structure of the valve core <NUM> includes a spherical portion <NUM> and a sealing plate <NUM> connected to each other. The spherical portion <NUM> is used to block the second valve port A, and the sealing plate <NUM> is used to block the first valve port B. A recessed hole 405a is provided in the side of the sealing plate <NUM> facing the spherical portion <NUM>, so that the spherical portion <NUM> can be partially inserted into the recessed hole 405a to be fixed, thereby facilitating the fixation of the spherical portion <NUM> and the sealing plate <NUM>. A protrusion is provided on another side of the sealing plate <NUM>, to be inserted into the return spring <NUM>, which plays a role of positioning, guiding, and facilitating the installation of the return spring <NUM>. At this time, the spherical portion <NUM> is not required to satisfy the blocking of the two valve ports at the same time, and the memory spring <NUM> is located between the end cover <NUM> and the sealing plate <NUM>.

Referring to <FIG> again, <FIG> is a sectional view showing the structure of a thermostatic valve according to a seventh example of the present application, with a first valve port B closed and a second valve port A opened.

Compared to the fourth to sixth examples, the difference in this example lies only in the structure of the valve element <NUM>. The valve core <NUM> is cylindrical in this example, and two end surfaces of the valve core <NUM> are used to seal the first valve port B and the second valve port A, respectively. A protrusion is also provided on the side of the valve core <NUM> facing the first valve port B, to be inserted into the return spring <NUM>, which has functions of positioning, guiding and facilitating the installation of the return spring <NUM>.

Referring to <FIG> continuously, <FIG> is a sectional view showing the structure of a thermostatic valve according to an eighth example of the present application, with a first valve port B opened and a second valve port A closed; <FIG> is a schematic view of the thermostatic valve after the temperature rises and the memory spring <NUM> is deformed in <FIG>, with the first valve port B closed and the second valve port A opened; <FIG> is a schematic view of the end cover <NUM> and the valve core <NUM>, the return spring <NUM>, and the memory spring <NUM> in <FIG> after installation; and <FIG> is a schematic perspective view of <FIG>.

Compared to the fourth to seventh examples, the second valve port A in this example is also provided in the end cover <NUM> (the end cover is not embodied as the seat switching structure), but the first outlet <NUM> is still provided in the side wall of the valve body <NUM>. At this time, an outlet passage 10d communicating the first outlet <NUM> with the second valve port A is provided in the end cover <NUM> and the valve body <NUM>, and the outlet passage 10d is actually equivalent to an "L" shape, as shown in <FIG>. The position of the second valve port A is similar to that of the fourth to seventh examples, which allows the valve core <NUM> to more conveniently move to realize blocking.

In addition, in this example, the end cover <NUM> is provided with a hole, and the thermostatic valve is further provided with a valve stem <NUM>. One end of the valve stem <NUM> can be inserted into the hole along the axial direction to be fixed, and another end of the valve stem <NUM> extends out of the end cover <NUM>. The other end of the valve stem <NUM> extending out of the end cover <NUM> can be inserted into the valve core <NUM> and is in sliding fit with the valve core <NUM>. In this way, the valve core <NUM> can move along the valve stem <NUM> during the movement process, thereby having good positioning and guiding effects.

As shown in <FIG> and <FIG>, an annular passage is formed at the outer periphery of the end cover <NUM>, which facilitates the medium flowing to the first outlet <NUM>. In <FIG>, the left end portion of the end cover <NUM> is used to block the left end port of the valve cavity 10a, the second valve port A is formed at the right end portion, and a connector is provided between the left end portion and the right end portion. The valve stem <NUM> is inserted into the connector from the second valve port A and enters the left end portion. The left end portion, the right end portion, and the connector of the end cover <NUM> are integrally formed, so that the structure is reliable, achieving the reliable installation of the valve stem <NUM> and the memory spring <NUM>, and these members can be assembled first and then installed into the valve cover 10a. Of course, the left end portion, the right end portion, and the connector of the end cover <NUM> may also be formed separately and then connected.

Obviously, the valve stem <NUM> is also applicable to other embodiments and examples. For the example where the first outlet <NUM> is provided in the end cover <NUM> with the seat switching structure, as shown in <FIG>, the valve stem can be inserted into the passage of the end cover <NUM>, and the end portion of the valve stem can be fixed to the side wall of the passage by a connector.

It should be noted that, in the eighth example, the valve stem <NUM> is fixed to the end cover <NUM>. It can be understood that the valve stem <NUM> can also be fixed to the valve core <NUM> and in sliding fit with the end cover <NUM>. In comparison, in case that the valve stem <NUM> is fixed to the end cover <NUM>, the valve core <NUM> can operate more smoothly and reliably.

Herein, the valve core <NUM> may be provided with a through hole to facilitate sliding along the valve stem <NUM>. In addition, a sealing piece <NUM>' is provided on the outer peripheral wall of the right end of the valve core <NUM>. The sealing piece <NUM>' serves as a first sealing portion for blocking the first valve port B. In order to install the return spring <NUM>, an annular groove is further provided in the outer peripheral wall of the right end of the valve core <NUM>. One end of the return spring <NUM> is inserted in the annular groove, another end of the return spring <NUM> abuts against the step of the small hole 10c, of course, the another end of the return spring <NUM> can also abut against the inner wall of the linear passage 10b or the end cavity wall of the valve cavity 10a, which has been described in the above examples, and will not be repeated here.

Regarding the sealing piece <NUM>', the sealing piece <NUM>' can also be integrally formed with the valve core <NUM>. As shown in <FIG> is a sectional view showing the structure of a thermostatic valve according to a ninth example of the present application, with a first valve port B closed and a second valve port A opened. When the sealing piece <NUM>' is integrally formed with the valve core <NUM>, it has a more reliable strength. The return spring <NUM> can directly abut against the sealing piece <NUM>'. The return spring <NUM> shown in <FIG> is pre-compressed on the step of the small hole 10c and the sealing piece <NUM>'. The valve core <NUM> can be variously designed in each embodiment of the present application, and the structure of the valve core <NUM> in each embodiment can be used interchangeably.

It should be noted that, for each embodiment, when the first inlet <NUM> is provided in the side wall of the valve body <NUM>, in order to improve the reliability of the movement of the valve core <NUM>, the valve core <NUM> may be designed such that at least a portion of the valve core <NUM> is in sliding fit with the inner wall of the valve cavity <NUM>, which can prevent impact on the valve core <NUM> or the memory spring <NUM> when the fluid flows in.

Referring to <FIG>, <FIG> is a sectional view showing the structure of a thermostatic valve according to a tenth example of the present application, with a first valve port B opened and a second valve port A closed; <FIG> is a schematic view of the thermostatic valve in <FIG> after the valve core is moved to the right, with the second valve port A opened and the first valve port B closed; and <FIG> is a schematic view of the valve core <NUM> in <FIG>.

In this example, the valve core <NUM> is movable axially along the valve cavity 10a, and a portion of the valve core <NUM> is in sliding fit with the inner wall of the valve cavity 10a. The first valve port B is located at the end cavity wall of the valve cavity 10a, that is, the axial cavity wall, and the second valve port A is located at the side cavity wall of the valve cavity 10a, that is, the radial cavity wall. In this solution, the first inlet <NUM> and the second valve port A are opposite to each other. Specifically, the inlet passage 10e communicating the first inlet <NUM> with the valve cavity 10a is opposite to the second valve port A and the outlet passage 10d. In this way, the passage between the first inlet <NUM> and the first outlet <NUM> is the linear passage. As shown in <FIG>, when the second valve port A is opened, the medium can flow out through the linear passage, and the response is faster.

The structure of the valve core <NUM> in this example is similar to that in the third example. The valve core <NUM> includes a sleeve portion <NUM> acting as a second sealing portion for blocking the second valve port A. The memory spring <NUM> is provided in the sleeve portion <NUM> and is located between the valve core <NUM> and the end cover <NUM>. Of course, it is also feasible to block the second valve port A by using the valve core <NUM> with other structures or the memory spring <NUM>.

In addition, in the tenth example, a notch 402c is provided at an edge of the open end of the sleeve portion <NUM>, to function as a flow guiding passage for guiding a medium into the sleeve portion <NUM>. As shown in <FIG>, when the sleeve portion <NUM> is used to block the second valve port A, the medium can enter the sleeve portion <NUM> through the position of the notch 402c, so that the memory spring <NUM> can be in contact with the heated medium and deform in time. It can be understood that the flow guiding passage is not limited to the notch 402c shown in the figure, for example, it may also be provided in the side wall or the bottom of the sleeve portion <NUM>.

It should be noted that the outlet passage 10d and the inlet passage 10e in this embodiment are oppositely arranged. When the sleeve portion <NUM> is in sliding fit with the inner wall of the valve cavity 10a, in order to avoid blocking the passage between the medium and the first valve port B, in <FIG>, a part of the outer wall of the sleeve portion <NUM> corresponding to the second valve port A is in sliding fit with the inner wall of the valve cavity 10a, and a gap is provided between the part, corresponding to the inlet passage 10e and the first inlet <NUM>, of the outer wall of the sleeve portion <NUM> and the inner wall of the valve cavity 10a, which can ensure that the medium can flow to the first valve port B. That is, the second sealing portion is only required to seal the second valve port A, and a gap is required to be provided between the portion, facing the inlet passage 10e, of the sleeve portion <NUM> and the inner wall of the valve cavity 10a. As shown in <FIG>, the central axis of the valve cavity 10a is offset from the central axis of the valve core <NUM>, and the portion, opposite to the inlet passage 10e, of the valve cavity 10a is concave. Of course, it can be understood that the valve cavity 10a may not be concave, and the valve core <NUM> may be provided as an eccentric structure relative to the axis. This manner of a portion of the valve core <NUM> in sliding fit with the inner wall of the valve cavity 10a not only satisfies stability and impact resistance, but also facilitates fluid flow.

In addition, in this example, a two-stage stepped hole is formed in the valve body <NUM> of the thermostatic valve, the largest hole is the valve cavity 10a, and a first valve port B is formed at a junction between the middle hole and the largest hole. In this way, the stroke of the valve core <NUM> moving to block the first valve port B can be shortened. Of course, it is also applicable to provide a stepped hole including a large hole and a small hole as in the above example.

The second inlet <NUM> and the second outlet <NUM> in this example are also opposite to each other, and a linear passage 10b is formed between the second inlet <NUM> and the second outlet <NUM>, and the return spring <NUM> penetrates the smallest hole and is compressed between the valve core <NUM> and the inner wall of the linear passage 10b. A groove allowing the end portion of the return spring <NUM> to be inserted can be provided in the inner wall of the linear passage 10b. Obviously, the end portion of the return spring <NUM> may also be compressed on the end wall of the valve cavity 10a, or a step may be provided at the smallest hole, and the end portion of the return spring <NUM> can be compressed on the step or the valve core <NUM>.

It should be noted that, in the above example, the formed valve cavity 10a is a cavity with an end port at one end, an end cover <NUM> is provided at the end port, and the memory spring <NUM> is provided between the end cover <NUM> and the valve core <NUM>. This method is convenient for machining the valve body <NUM> to form the valve cavity 10a, but it can be understood that the structure of the valve cavity 10a is not limited thereto. For example, when using a casting process, two ends of the valve cavity 10a may not have end ports, and no end covers are provided. Then, the memory spring <NUM> and the return spring <NUM> (in the first embodiment) may be provided between the cavity wall of the valve cavity 10a and the valve core <NUM>.

It can be seen from the example with the preset opening degree that the purpose of setting the two-stage step is to use the characteristic of the memory spring <NUM>, to allow the memory spring <NUM> to switch from the initial position to the working position after being heated, expanded and deformed, and to be kept at the working position. Therefore, the solutions for realizing the purpose is not limited to providing the two-stage step. For example, an annular groove is provided at the end portion of the valve core <NUM>, and an end portion of the memory spring <NUM> is provided in the annular groove, and after the temperature rises, this end portion of the memory spring <NUM> is detached from the annular groove and abuts against other position as the working position, which can also achieve the purpose of setting the initial preset opening degree.

In the above example, the control element for controlling the movement of the valve core <NUM> of the thermostatic valve is the memory spring <NUM>. Compared with the solution that the spring is surrounded around the thermal actuator, the response time of the memory spring <NUM> is faster, and the second valve port A can be opened in time to switch the medium to another flow path. When being applied to the cooler and the transmission, it can improve the performance of the transmission and prevent damages to the transmission.

Further, in this case, a thermal actuator is not required to be additionally provided in the thermostatic valve, the structure is simple and the installation is convenient, which allows the whole thermostatic valve lighter in weight and smaller in volume.

It should be noted that in the above embodiments and examples, as an example, the valve body <NUM> is provided with the first valve port B and the second valve port A. It can be understood that the second valve port A may not be provided, that is the second valve port A that can be opened and closed is not provided, but the passage between the first outlet <NUM> and the valve cavity 10a is through. Taking the application to the transmission and the cooler as an example, when the first valve port B is closed, the medium (such as lubricating oil) can directly flow to the cooler; when the first valve port B is opened, even if there is no second valve port A and only the outlet passage in communication with the first outlet <NUM> is provided, because the cooler is in communication with the first outlet <NUM>, the flow resistance of the flow path through the first outlet <NUM> will be greater than the flow resistance of the flow path directly flowing to the second outlet <NUM> through the first valve port B. Therefore, the medium will mostly flow through the first valve port B to the second outlet <NUM>. Of course, by providing the second valve port A and switching the opening and closing states of the second valve port A and the first valve port B, it can more clearly distribute the flow paths of the medium under different requirements and reduce the system internal leakage.

In addition, when the second valve port A is not provided, in the above embodiment with the initial position and working position, it can be designed in a way that when the memory spring <NUM> is at the initial position, the first valve port B is closed, so that the lubricating oil can be directly flows into the cooler from the first outlet <NUM> to fill the lubricating oil in the initial state. At the same time, a second inlet <NUM> should be provided, and the first valve port B will also be in communication with the second inlet <NUM>, so that the lubricating oil flowing in from the second inlet <NUM> can also fill the passage between the first valve port B and the transmission, to complete the oil filling process of the whole system.

When the second valve port A is provided, the first valve port B may have a preset opening degree as described in the above embodiment, and may also be closed. When the first valve port B is closed, the valve body <NUM> of the thermostatic valve is also preferably provided with the second inlet <NUM> in communication with the second outlet <NUM>, so that the lubricating oil flowing in from the second inlet <NUM> can also fill the passage between the first valve port B and the transmission. Of course, when the first valve port B has a preset opening degree at the initial position, the passage between the first valve port B and the transmission can be filled. The solution is not limited to providing the second inlet <NUM> in the valve body <NUM>, and the outlet of the cooler can also be connected to the transmission through other passages.

Regardless of whether or not the second valve port A is provided, in order to facilitate filling the cooler in the initial state, it can be set as follows: a distance between the valve core <NUM> and the first valve port B when the memory spring <NUM> is at the initial position is smaller than the distance between the valve core <NUM> and the first valve port B when the memory spring is at the working position and the temperature is below a specified value. In this way, when the memory spring <NUM> is below the temperature with the specified value, the length of the memory spring <NUM> changes, so that the first valve port B and/or the second valve port A can be adjusted to have different opening degrees at the initial position and working position.

Claim 1:
A thermostatic valve comprising an end cover (<NUM>), a valve body (<NUM>), and a valve core (<NUM>) located in a valve cavity (10a) of the valve body (<NUM>), wherein the thermostatic valve has a first outlet (<NUM>), a second outlet (<NUM>), and a first inlet (<NUM>) which is in communication with the valve cavity (10a), the valve body (<NUM>) is further provided with a first valve port (B) configured to communicate the valve cavity (10a) with the second outlet (<NUM>), and during a movement of the valve core (<NUM>), the valve core (<NUM>) is configured to open or close the first valve port (B); wherein
a return spring (<NUM>) and a memory spring (<NUM>) are further provided in the valve cavity (10a), the memory spring (<NUM>) is made of a memory alloy; the return spring (<NUM>) is configured to provide a return force to allow the valve core (<NUM>) to open the first valve port (B); the memory spring (<NUM>) has one end in contact with one end of the valve core (<NUM>), and another end in contact with the end cover (<NUM>), and when a temperature rises to a specified value, the memory spring (<NUM>) is configured to generate an elastic force to drive the valve core (<NUM>) to move against the return force to close the first valve port (B); and
the first inlet (<NUM>) is provided in a side wall of the valve body (<NUM>),
the thermostatic valve being characterized in that it is further provided with a second valve port (A), the second valve port (A) is provided in a side cavity wall of the valve cavity (10a), and when the temperature is less than the specified value, the memory spring (<NUM>) is in a compressed and tight state and in correspondence to the position of the second valve port (A), to block the second valve port (A), wherein the second valve port (A) is for communicating the valve cavity (10a) with the first outlet (<NUM>).