JPH07104732B2 - Hot water mixing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hot and cold water mixing apparatus for adjusting a mixing ratio of hot water and water to obtain hot water having an appropriate temperature.

[Prior art]

Conventionally, one shaft is provided with a hot water valve body and a water valve body 1
A shaft type hot and cold water mixing valve has a water valve seat communicating with a water inlet and a hot water valve seat communicating with the hot water inlet in a mixing chamber, as described in, for example, JP-A-60-249782. The water valve body that is opened to face each other and that engages with the water valve seat, and the hot water valve body that engages with the hot water valve seat are slidably arranged on one valve shaft, Positions of the inner ends of the two valve bodies facing each other are regulated by stoppers, and the two valve bodies are biased by springs in the opposing directions.

When one end of the valve shaft is pressed by a stepping motor via a cam etc. and the valve shaft is moved in the axial direction to adjust the opening of each of the water valve body and the hot water valve body to lower the hot water supply temperature. Increases the opening degree of the water valve element and decreases the opening degree of the hot water valve element to decrease the hot water quantity Q _H , while increasing the water quantity Q _C to lower the hot water temperature and raise the hot water supply temperature. At this time, the opening degree of the water valve body is made small and the opening degree of the hot water valve body is made large to increase the hot water quantity Q _H while decreasing the water quantity Q _C to raise the hot water temperature. By adjusting the mixing ratio b (b = Q _C / Q _H ) with the hot water of appropriate temperature.

[Problems to be Solved by the Invention]

However, in the above-mentioned conventional single-axis hot and cold water mixing valve, the operation amount by the stepping motor is appropriately determined in order to adjust the opening degree of the water valve element and the hot water valve element to obtain a predetermined mixing ratio. However, there are problems that the hot water temperature hunts and it takes time to stabilize.

Further, the relationship between the operation amount of the stepping motor (that is, the rotation angle of the drive shaft) θ and the mixing ratio b of hot water and water is expressed by b = k × θ.
Since (k is a coefficient depending on the pressure of hot water) is linear, the pressure p of hot water is p ₁ (k = k ₁ ), p ₂ (k = k ₂ ), p ₃ (k
= K ₂ ) (However, p ₁ <p ₂ <p ₃ ) (See Fig. 5)
In this case, since k ₁ <k ₂ <k ₃ , the mixing ratio b is b ₁
From the change to b ₂ (b ₁ <b ₂ ) Δb (Δb = b ₂
Variation [Delta] [theta] of the operation amount θ relative -b ₁₎ is, p = p Δθ ₁ when _1, p = Δθ ₂ when p _2, p = p Δθ ₃ when the ₃ (delta
θ ₁ > Δθ ₂ > Δθ ₃ ), and there is a problem that the change amount Δθ of the operation amount θ of the stepping motor changes when the hot water pressure p changes.

An object of the present invention is to provide a hot and cold water mixing apparatus which can prevent hunting from occurring and can determine a reliable operation amount of a stepping motor or the like with a fast control speed.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the hot and cold water mixing apparatus of the present invention is provided with a valve shaft, which is axially moved by the rotational force of a drive source such as a stepping motor transmitted by a cam or the like, and water provided on the valve shaft. A valve body for hot water and a valve body for hot water, and a valve seat for water and a valve seat for hot water opened in the mixing chamber, and the valve body for water and the valve body for hot water are moved to move the valve seat for water and the valve for hot water. In a 1-axis hot and cold water mixing device that controls the outlet water temperature by adjusting the amount of water flowing into the mixing chamber and the amount of hot water by controlling the opening of the seat, mixing when the amounts of hot water Q _H and Q _C are mixed Between the ratio b (b = Q _C / Q _H ) and the operation amount θ which is the rotation angle of the drive shaft of the drive source, b = K
It has a relationship of × a ^θ .

Note that K is a coefficient determined by the pressure of hot water and water, and a is a constant determined by the mixing device.

[Action]

In the hot and cold water mixing apparatus of the present invention configured as described above, from the current mixing ratio b ₁ (operation amount θ = θ ₁ ) to the target mixing ratio b _s.
When changing to (movement amount θ = θs), the variation amount Δθ (Δθ = θ _s −θ ₁ ) of the movement amount θ is Δθ = [log (b _s / b ₁ ) / log
a].

In addition, target mixed hot water temperature T _S , current mixed hot water temperature T _M , hot water temperature T _H , water temperature
In T _C , the relationship of b ₁ = (T _H −T _M ) / (T _M −T _C ) b _s = (T _H −T _S ) / (T _S −T _C ) holds, so the target mixture Hot water temperature T _S , current mixed hot water temperature
From T _M , the hot water temperature T _H , and the water temperature T _C, it is possible to obtain the variation amount Δθ for rotating the drive shaft regardless of the value of the current operation amount θ ₁ .

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, hot water flows from a hot water inlet 1 through a check valve 2 into a pressure balancer 3, and from the pressure balancer 3 hot water mixing valve 5
Flows into the hot water flow path 4.

Water flows from the water inlet 11 through the check valve 12 into the pressure balancer 3, and then flows from the pressure balancer 3 into the water flow path 14 of the hot and cold water mixing valve 5.

The hot and cold water mixing valve 5 is provided with a hot water valve seat 8 communicating with the hot water flow path 4 and opening to the mixing chamber 9, and a water valve seat 18 communicating with the water flow path 14 and opening to the mixing chamber 9. The hot water valve body 7 engaging with the hot water valve seat 8 mounted facing the valve shaft 6 and the water valve body 17 engaging with the water valve seat 18 are provided in the mixing chamber 9. is set up.

The valve shaft 6 is moved in the axial direction by the rotation of the drive shaft of the stepping motor 10 installed outside the hot and cold water mixing valve 5 via cams, gears, etc. (not shown), and the hot water of the hot water valve body 7 is moved. The opening degree of the water valve body 17 is adjusted by adjusting the opening degree of the water valve seat 8 and the opening degree of the water valve body 17 with respect to the water valve seat 18. When the opening degree of the hot water valve body 7 becomes small, the opening degree of the water valve body 17 is made large.

The hot water mixed in the mixing chamber 9 is discharged to the shower or another hot water tap through the flow rate sensor 20 and the flow rate adjusting water stop valve 21 driven by the stepping motor 22.

Also, the hot water flow path 4 of the hot and cold water mixing valve 5 detects the bathing temperature T _H bathing thermistor 23 is installed, detects the incoming water temperature T _C in the water passage 14 is installed incoming water thermistor 24,
A hot water outlet thermistor 25 is installed in the outlet side flow path of the mixing chamber 5 to detect the hot water outlet temperature, that is, the present temperature hot water temperature T _M. The temperature detection signal and the detection signal from the flow rate sensor 20 are a controller (not shown). And the operation amount of the stepping motors 10 and 22 is controlled by the output signal from the controller.

Here, the mixing ratio b (b when the amount of hot water Q _H and the amount of water Q _C are mixed
= Q _C / Q _H ) and the amount of movement θ, which is the rotation angle of the drive shaft of the stepping motor 10, are controlled by the characteristic (see FIG. 2) that b = K × a ^θ is established. is there.

Note that K is a coefficient determined by the pressure of hot water and water, and a is a constant determined by the mixing device.

Here, in order to have the relationship of b = K × a ^θ , since the opening / closing operation direction of the valve is opposite, the water amount Q and the water side valve are respectively expressed by the exponential function of the operation amount θ. _It is sufficient if it has the characteristics of _C and the quantity of hot water Q _H. That is, the valve on the water side may be Q _C = K _C × A _C ^θ The valve on the hot water side may be Q _H = K _H × ^{ΔA −θ} _H ▼.

However, K _C is a coefficient determined by the pressure of water, K _H is a coefficient determined by the pressure of hot water, A _C is a constant determined by the valve on the water side, and A _H is a constant determined by the valve on the hot water side.

From the above characteristics, b = Q _C / Q _H = (K _C × A _C ^θ ) / (K _H × ▲
A ^−θ _H ▼) = (K _C / K _H ) × (A _C × A _H ) ^θ = K × a ^θ However, K = (K _C / K _H ), a = (A _C × A _H ).

In order for the water side valve to have the above-mentioned characteristics, the radius of the water valve seat 18 is R _C , the distance moved from the fully closed position of the water valve body 17 in the opening direction is x, and the water valve body is Assuming that the radius at a position x from the fully closed position of 17 is r _C , the water amount Q _C is the opening area D _C = πR _C ² −πr formed between the water valve seat 18 and the water valve body 17.
_Since it is proportional to _C ² , Q _C = G × D _C = G × (πR _C ² −πr _C ² ) = K _C × A _C ^θ .

Since the operation amount θ, that is, the rotation angle of the valve shaft 6 and the moving distance x of the water valve body 17 are in a proportional relationship, when θ = f · x, Q _C = G × (πR _C ² −πr _C ² ) = K _C × A _C ^θ = K _C × ▲ A ^{f · x} _C ▼ Therefore, πr _C ² = πR _C ² − (K _C / G) × ▲ A ^{f · x} _C ▼ That is, r _C = The water valve element 17 may be formed in a shape represented by {R _C ² (K _C / πG) × ∇A ^{f · x} _C ▼} ^1/2 .

Similarly, for the hot water valve, the hot water valve body 7 may be formed in a shape represented by r _H = { _RH ² − (K _H / πG) × ▲ A ^{f · x} _H ▼} ^1/2. It is a thing.

However, R _H is the radius of the hot water valve seat 8, r _C is the radius at the position of the distance x from the fully closed position of the hot water valve body 17, and since it is coaxial, the movement amount θ and the movement distance x are the water side. Is equivalent to the valve.

In the control of the above characteristics, the current mixing ratio b ₁ (operation amount θ = θ
₁ ) to the target mixture ratio b _s (movement amount θ = θ _s ), the variation amount Δθ is Δθ = θ _s −θ ₁ , Therefore, the variation amount Δθ of the operation amount θ is obtained by Δθ = [log (b _s / b ₁ ) / log a].

Further, in the target mixed hot water temperature T _S , the current mixed hot water temperature T _M , the incoming hot water temperature T _H , and the incoming hot water temperature T _C , T _M (Q _H + Q _C ) = T _H · Q _H + T _C · Q _C , Q _C / Q _H = (T _H −T _M ) / (T _M −T _C ), and b ₁ = (T _H −T _M ) / (T _M −T _C ) b _s = (T _H −T The relationship of _S ) / (T _S −T _C ) is established.

Therefore, target mixed hot water temperature T _S , current mixed hot water temperature T _M , hot water temperature
From T _H and the water temperature T _C , it is possible to obtain the fluctuation amount Δθ for rotating the drive shaft.

Here, in FIG. 3, the hot water supply pressure p is p ₁ (at this time, K = K ₁ ), p ₂ (also K = K ₂ ), p ₃ (also K
= K ₂ ) (where p ₁ <p ₂ <p ₃ ), the variation Δθ of the operation amount θ is independent of the pressure p or the coefficient K as described above, and the pressure p fluctuates. Even in this case, if the current mixture ratio b ₁ and the target mixture ratio b _s are equal, the fluctuation amount Δθ is always constant.

In other words, regardless of the hot water pressure p, if the current mixing ratio b ₁ and the target mixing ratio b _s are determined, that is, the set target mixing hot water temperature is set.
The variation amount Δθ is determined from T _S and the detected current mixed hot water temperature T _M , hot water temperature T _H , and water temperature T _C.

An example of the characteristics of the hot water amount Q _H and the water amount Q _C such that the above equation b = K × a ^θ is satisfied
It is shown in FIGS. 4 (a) and 4 (b).

According to the above structure, since the rotation angle of the drive shaft of the stepping motor 10 required to the target mixed hot water temperature T _S is determined, it is converged to the target mixed hot water temperature T _S with the maximum speed level not hunting You can

〔The invention's effect〕

Since the present invention is configured as described above, it has the following effects.

If the current mixing ratio and the target mixing ratio are determined regardless of the hot and cold water pressure, that is, the target mixing hot water temperature to be set and the detected current hot water mixing temperature, hot water temperature, and water temperature change in the rotation angle of the drive shaft. Since the amount is required, it becomes easy to set the drive amount of the drive source,
In addition, stable control can be performed.

Further, since the rotation angle of the drive shaft required to reach the target mixed hot water temperature is obtained, the target mixed hot water temperature can be converged to the target mixed hot water temperature at the maximum speed without hunting.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a hot and cold water mixing apparatus to which the present invention is applied,
FIG. 2 is a control characteristic diagram according to the present invention, FIG. 3 is a control characteristic diagram when pressures are different, FIG. 4 (a) and FIG.
FIG. 5B is a characteristic diagram of the amount of hot water and the amount of water, and FIG. 5 is a conventional control characteristic diagram. 4 ... hot water flow path, 6 ... valve shaft, 7 ... hot water valve body, 8 ... hot water valve seat, 9 ... mixing chamber, 14 ... water flow path, 17 ... water valve body, 18 …… Water valve seat, 22 …… Hot water thermistor, 23 …… Water incoming thermistor, 24 …… Hot water thermistor.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukihiro Shinma 32 Akashi-cho, Chuo-ku, Kobe, Hyogo Prefecture Stock company Noritsu (72) Inventor Hidehito Ichimaru 32 Akashi-cho, Chuo-ku, Kobe City Hyogo Prefecture Noritsu (56) Reference JP-A-62-267801 (JP, A) JP-A-62-267802 (JP, A)

Claims (1)

[Claims] Claim: What is claimed is: 1. A valve shaft axially moved by transmitting a rotational force of a drive source such as a stepping motor, a valve body for water and a valve body for hot water provided on the valve shaft, and a mixing chamber. With a water valve seat and a hot water valve seat that are opened, by moving the water valve body and the hot water valve body to control the opening degree of the water valve seat and the hot water valve seat, In a single-axis hot-water mixing apparatus that controls the hot water temperature by adjusting the amount of inflowing water and the amount of hot water, between the mixing ratio b of hot water and water and the operation amount θ that is the rotation angle of the drive shaft of the drive source. , K is a coefficient determined by the pressure of hot water and water,
A hot and cold water mixing apparatus having a relationship of b = K × a ^θ when a is a constant determined by the mixing apparatus.