JPH0338918B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is mainly used in the manufacturing industry of automobiles and machine tools, and is used to clean objects to be cleaned such as mechanical parts using solvent vapor. The present invention relates to an improvement of a heat pump type steam cleaning device that performs this and a method of operating the device.

(Prior art) A conventional heat pump type steam cleaning device is usually formed of a steam cleaning tank 1, a heat pump 2, etc., as shown in FIGS. 2 and 3.
The system is configured to recover the heat of condensation of the solvent vapor and heat the solvent liquid.

That is, in FIG. 2, the steam cleaning tank 1 is formed of a cleaning section 1a in which solvent vapor exists and a solvent storage section 1b that stores a solvent solution. A pipe 4 and a heater 5 are provided in the solvent storage section 1b, respectively.

The heat pump 2 is composed of a compressor 2a, a condenser 2b, an expansion valve 2c, an evaporator 2d, etc., and a cooling water circulation pump is interposed in the heat exchange pipe 6 of the evaporator 2d to connect the cooling pipe 4. are connected in an annular manner, and the condenser 2b is configured within the solvent liquid reservoir 1b of the steam cleaning tank 1.

Therefore, the heater 5 or the heat pump condenser 2b
When the solvent liquid is heated by the heat exchange tube 8', solvent vapor is generated. The generated solvent vapor fills the cleaning section 1a, is cooled by the object to be cleaned 10 and the cooling pipe 4, and is sequentially condensed. At this time, the condensation heat given to the cooling pipe 4 is transferred to the cooling water and the evaporator 2.
d to the heat medium of the heat pump 2,
After the heat medium is heated and pressurized by the heat pump, it is reused to heat the solvent solution. In this way, the solvent solution is heated, evaporated and condensed by a so-called thermal closed cycle.

On the other hand, the solvent liquid condensed on the outer surface of the object to be cleaned 10 performs a cleaning action on the object while flowing down along the outer surface of the object, and the contaminated solvent liquid after cleaning is transferred to the object to be cleaned 10.
0 is stored in the storage section 1b below.

The conventional heat pump type steam cleaning device can quickly and reliably clean the object 10 to be cleaned, and has excellent practical effects.

However, the heat pump type steam cleaning apparatus shown in FIG. 2 still has many problems as described below.

(1) Since the heat exchange tube 8' of the heat pump condenser 2b is immersed into the solvent liquid storage part 1b, the volume and the amount of solvent stored in the storage part 1b are inevitably large, and the heat capacity becomes large. As a result, it takes a long time to start up the cleaning device, and the responsiveness to fluctuations in cleaning load is low.

(2) In addition, since the solvent vapor is condensed only in the cooling pipe 4 and is not equipped with a cooler or a heat radiator to replace it, the solvent vapor may leak from the steam cleaning tank 1 when the equipment is stopped or when the cleaning load suddenly decreases. It is easy to overflow to the outside.

(3) The auxiliary heater 5 and heat exchange pipe 8' are removed from the steam cleaning tank 1.
Since the tank is arranged in the solvent solution storage section 1b, inspection of the heat transfer surface, tank bottom, and tank wall becomes extremely inconvenient.

On the other hand, the heat pump type steam cleaning device shown in FIG. 3 was developed to improve the above-mentioned problems.
d is made independent from the steam cleaning tank 1, and the solvent liquid in the storage part 1b is circulated to the heat exchange pipe 8 by the circulation pump 9, and the heat pump 2 is used for cooling the solvent vapor.
A cooling device 3 is provided in parallel with the evaporator 2d, and a refrigerant tank 13 is further provided in the heat pump side cooling system.

By adopting the configuration as shown in FIG. 3, the storage portion 1b of the steam cleaning tank 1 can be made relatively small, its heat capacity is reduced, and the start-up time can be shortened. Further, after the operation is stopped, the cooling water is switched from the evaporator 2d to the cooling device 3 side, thereby preventing solvent vapor from flowing out of the tank. Furthermore, the balance between the amount of heating of the solvent liquid and the amount of cooling heat of the solvent vapor due to sudden changes in the cleaning load is balanced by the refrigerant tank 13.

However, the improved steam cleaning apparatus still has various problems as described below.

(1) Cooling water is evenly supplied to the cooling pipe group 4 provided on the inner wall surface of the cleaning section 1a of the steam cleaning tank 1, but during regular operation of the device, the cooling pipes located above The cooling load applied to No. 4 is relatively small.

As a result, there is a surplus of cooling water flowing through the upper cooling pipe 4, increasing energy consumption.

(2) If a heater 5 is installed in the steam cleaning tank 1 and the equipment is started after being stopped for a long time, the heater 5
However, solid matter in the solvent may deposit and adhere to the outer surface of the heater.
The heater is likely to burn out, and inspection and cleaning of the bottom of the tank become difficult.

(3) With only the amount of heat held by the refrigerant tank 13, it becomes difficult to ensure a sufficient solvent vapor level when the load suddenly increases, and stable cleaning cannot be performed.

(Problems to be Solved by the Invention) The present invention aims to solve the above-mentioned problems (1) to (3) in the conventional heat pump type steam cleaning equipment. This makes it possible to reduce the energy consumption required for circulating the cooling water in the pipe 4, and to ensure a stable amount of solvent vapor even when the equipment is stopped or the load suddenly changes. The present invention provides a heat pump type steam cleaning device and a method of operating the same, which eliminates heating and eliminates troubles such as burnout of the heater.

(Means for Solving the Problems) The heat pump type steam cleaning apparatus and the operating method thereof of the present invention are configured as follows in order to achieve the above object.

That is, in the steam cleaning device of the first invention, the first cooling pipe group 4 is arranged above the standard solvent vapor level Ls, which is the upper limit level of solvent vapor during steady operation.
and a steam cleaning tank 1 having a second cooling pipe group 4' disposed thereunder; an evaporator 2d for cooling the refrigerant flowing into the second cooling pipe group 4'; and the steam cleaning tank 1.
a heat pump 2 equipped with a condenser 2b that heats the solvent liquid in the refrigerant tank 13; a cooling device 3 that cools the refrigerant flowing into the cooling pipe group 4; the solvent vapor level in the steam cleaning tank 1 is the standard solvent vapor level Ls;
a first steam level control mechanism 25 that detects this and activates the cooling system using the first cooling pipe group 4 when the solvent vapor level in the steam cleaning tank 1 rises by a predetermined amount; When the drop is below a predetermined amount, this is detected and heater 2 is activated.
2, and a second steam level control mechanism 26 that operates the second steam level control mechanism 26. In such a device, it is preferable that the first steam level control mechanism 25 is configured to stop or operate the heat pump 2 at a partial load simultaneously with the operation of the cooling system by the first cooling pipe group 4.

The operating method of the second invention also includes a first cooling pipe group 4 arranged above the standard solvent vapor level Ls, which is the upper limit level of solvent vapor during steady operation, in the steam cleaning tank 1, and a first cooling pipe group 4 arranged below it. 2 cooling tube group 4'
is provided, and during steady operation of the device, only the cooling system by the second cooling pipe group 4' is operated, and
The heat pump 2 recovers the heat of the refrigerant flowing out from the second cooling pipe group 4' and uses the recovered heat to heat the solvent liquid in the steam cleaning tank 1, so that the solvent vapor level becomes the standard solvent vapor level Ls. When the temperature rises by a predetermined amount or when the device operation is stopped, the cooling system using the first cooling pipe group 4 is activated, and the refrigerant flowing into the cooling pipe group 4 is cooled by the cooling device 3 provided separately from the heat pump 2. Heat pump 2 is stopped or operated at partial load, and the solvent vapor level is the standard solvent vapor level.
When the refrigerant is lowered by a predetermined amount from Ls or when the device is started up, the refrigerant flowing out from the second cooling pipe group 4' is auxiliary heated by the heater 22 of the refrigerant tank 13 interposed in the outflow pipe line 18, and the refrigerant is heated by the heat pump 2. This is to increase the amount of heating of the solvent solution.

(Function) The solvent solution in the steam cleaning tank 1 is heated by the condenser 2b of the heat pump 2 to generate steam, and the cleaning section 1a is filled with this solvent vapor.

When the device is in steady operation, the upper limit level of the solvent vapor in the steam cleaning tank 1 is maintained at a level a predetermined amount below the top surface of the steam cleaning tank 1, that is, the standard solvent vapor level Ls. be done.

In other words, during steady operation, only the cooling system by the second cooling pipe group 4' below the standard solvent vapor level Ls is operated, and the solvent vapor in the cleaning section 1a is absorbed by the object to be cleaned and the second cooling pipe group. It will condense and liquefy on the outer surface of 4' and its upper level will be maintained at the standard solvent vapor level.

At this time, the heat of condensation given to the second cooling pipe group 4' is recovered by the heat pump 2 via the refrigerant, and the recovered heat is used as heat of evaporation of the solvent liquid.

If the device operation is stopped in such a state or the cleaning load is suddenly reduced, the upper limit level of the solvent vapor will rise.

Then, when this solvent vapor level rises by a predetermined amount from the standard solvent vapor level Ls, the first vapor level control mechanism 25 detects this and operates the cooling system by the first cooling pipe group 4. 4 begins condensation of the solvent vapor. As a result, the solvent vapor level is prevented from rising, and the solvent vapor is prevented from flowing out from the vapor cleaning tank 1. In addition, at this time, the heat pump 2 is stopped or operated at partial load as necessary. The heat pump 2 is controlled by the first steam level control mechanism 25.
It is preferable to perform this at the same time as the operation of the cooling system using the cooling pipe group 4.

Additionally, when the cleaning load increases rapidly during operation, the steam level decreases.

And the vapor level is the standard solvent vapor level Ls
When the temperature drops further by a predetermined amount, the second steam level control mechanism 26 detects this and operates the heater 22 of the refrigerant tank 13, and the auxiliary heat amount by the heater 22 is supplied to the heat pump 2. As a result, heating of the solvent liquid by the heat pump 2 is promoted, and the dropped vapor level is quickly restored. Note that this effect is similarly performed when the device is started up, and the steam level is quickly raised at the time of start-up.

(Example) Hereinafter, an example of the present invention will be specifically described based on FIG. 1.

First, the configuration of the heat pump type steam cleaning device according to the present invention will be explained.

As shown in FIG. 1, the steam cleaning apparatus of this embodiment includes a steam cleaning tank 1, a heat pump 2, and first and second steam level control mechanisms 25 and 26.

The steam cleaning tank 1 is formed with a cleaning section 1a for cleaning the object 10 to be cleaned and a storage section 1b for storing a predetermined amount of solvent solution.

Inside the cleaning section 1a, first and second cooling pipe groups 4, 4' are arranged along the peripheral wall of the tank 1.
The first cooling pipe group 4 consists of a set of coiled cooling pipes 4a, and is set at a standard solvent vapor level Ls (line segment S-
It is placed above the level indicated by S). Second
The cooling pipe group 4' includes two sets of coiled cooling pipes 4b and 4c.
and is located above the standard solvent vapor level Ls. The ends of both cooling pipes 4b and 4c are connected to each other. In addition, each cooling pipe group 4,
The number of cooling pipes constituting 4' is appropriately set depending on the cleaning capacity, tank shape, etc.

The first cooling pipe group 4 is connected to a cooling tower 3 as a cooling device and a refrigerant circulation pipe line in which a circulation pump 16 is interposed. 4, that is, it can be supplied and circulated to the cooling pipe 4a.

The heat pump 2 includes a compressor 2b and a condenser 2.
b, an expansion valve 2c, an evaporator 2d, etc., and a heat exchange pipe 6 of the evaporator 2d is connected to a refrigerant tank 13.
The heat exchange pipe 8 of the condenser 2b is connected to the middle and lower cooling pipes 4b and 4c via the refrigerant outflow pipe 18 with the circulation pump 7 interposed therebetween and the refrigerant inflow pipe 19 with the circulation pump 7 interposed therebetween. and the solvent liquid storage part 1b of the steam cleaning tank 1 via a pipe line 21 with a circulation pump 9 interposed therein.
communicated within.

An electric heater or a steam heater 22 is provided inside the refrigerant tank 13 interposed in the pipe line 18 in order to provide the cooling water 12 with an amount of supplementary heat necessary at startup or during high load.

The first steam level control mechanism 25 includes a first steam level detector 14 disposed near the upper part of the cooling pipe 4a, a circulation pump 16, and a compressor 2a of the heat pump 2.
The upper limit level of the solvent vapor in the tank 1 is a predetermined amount higher than the standard solvent vapor level Ls (the level shown by the line segment S'-S' in Fig. 1). When this is reached, the detector 14 detects this, and the controller 23 operates the cooling system of the first cooling group 4 and stops or partially operates the heat pump 2a.

The second steam level control mechanism 26 includes cooling pipes 4b,
4c, and a controller 24 for controlling a heater 22, and a controller 24 for controlling a heater 22. When the temperature drops to the level (the level shown by the line segment S''-S'' in FIG. 1) or below this level, the detector 15 detects this and the controller 24 turns on the heater 22. It's starting to work.

Next, the operating method according to the present invention will be explained with respect to a cleaning device having an upper air configuration.

The solvent heated in the condenser 2b of the heat pump 2 is returned to the steam cleaning tank 1 through the pipe line 20 in the state of steam or a gas-liquid mixture, and the solvent vapor is returned to the cleaning section 1a in the steam cleaning tank 1. Fill up. The standard level Ls of solvent vapor in the cleaning section 1a is:
During steady operation of the apparatus, the solvent vapor density is approximately the same as the line segment SS, and the solvent vapor density in the space above the line segment SS is extremely low. On the other hand, when the cleaning load on the equipment suddenly decreases, the heating amount of the solvent liquid becomes larger than the cooling amount of the solvent vapor, and the solvent vapor level increases and the approximate line S′−
It reaches the line S′.

A part of the solvent vapor in the cleaning section 1a is cooled and condensed on the outer surface of the object to be cleaned 10, and washes the outer surface of the object while flowing down.

Further, the solvent solution contaminated by cleaning the outer surface of the article is stored in a storage section below the object to be cleaned 10.

Further, the other solvent vapor in the cleaning section 1a is cooled by the middle and lower cooling pipes 4b and 4c, and the condensed solvent liquid drips into the storage section 1b. The heat of condensation given to the cooling pipes 4b and 4c is recovered by the heat medium of the heat pump via the cooling water 12 circulated by the cooling water circulation pump 7, and is converted into a solvent liquid in the heat pump condenser 2b. Reused for heating. In the steady operating state of the apparatus, since the solvent vapor level L is at the line segment S-S, it goes without saying that the cooling pipe 4a located above this level is in a non-operational state. That is, the cooling pipes 4a included in the system of the cooling tower 3 are arranged above the standard solvent vapor level Ls during steady operation.

By the way, if the cleaning load suddenly decreases,
The solvent vapor level increases as described above. When the solvent vapor level rises to about the line segment S'-S', the first vapor level detector 14 installed at that level
detects this and sets the compressor 2a of the heat pump 2 to partial load operation or stops the operation via the controller 23, and also controls the cooling tower 3 and the pump 1.
6 to operate the cooling pipe 4a,
The solvent vapor present in the location zone is condensed.
This operation prevents the solvent vapor from overflowing to the outside of the steam cleaning tank, and maintains the solvent vapor level in the tank at the optimal position level for operation (line segment S-S).

Conversely, when the equipment is started up or when the cleaning load increases rapidly, the solvent vapor level decreases. When the solvent vapor level falls to the level of the cooling pipe 4c (line segment S''-S''), the second vapor level detector 15 installed at that level detects this, and the refrigerant tank is detected via the controller 24. Thirteen heaters 22 are activated.
This heats the cooling water and heat pump 2
The amount of heat given to the heat pump heat medium in the evaporator 2d increases, and the amount of heat discharged from the condenser 2b increases. As a result, the evaporation of the solvent liquid from the reservoir 1b is promoted, and the solvent vapor level in the steam cleaning tank 1 is restored to the standard level (S-S). It goes without saying that the heater 22 is operated simultaneously with the heat pump 2 when the apparatus is started up.

As mentioned above, in this embodiment, three sets of cooling pipes 4a, 4b, and 4c are arranged, and the upper limit detector 14 for the solvent vapor level is placed near the top of the cooling pipe 4a, and the solvent vapor level The lower limit detectors 15 are disposed at intermediate positions between the cooling pipes 4b and 4c, respectively.
It is also possible to install it near the bottom position of c.

Also, two sets of cooling pipes 4a and 4b are arranged, with the upper limit detector 14 located near the top of the upper cooling pipe 4a, and the lower limit detector 15 located at an intermediate position between the cooling pipes 4a and 4b or at the lower end. It is also possible to install it near the lowest position of the cooling pipe 4b.

(Effect of the invention) In the present invention, as mentioned above, the cooling pipes arranged in the steam cleaning tank are divided into two groups, and during steady operation of the device, the cooling pipes arranged in the lower part of the group are divided into two groups. Since the configuration is such that only one cooling pipe system is operated, energy consumption in the cooling system can be significantly reduced, and stable and economical operation can be performed.

In addition, when the cleaning load suddenly decreases, the other cooling pipes installed in the upper position are activated and the cooling device 3 cools the refrigerant, which prevents solvent vapor from flowing out of the cleaning tank. etc. will be completely eliminated.

Furthermore, when the cleaning load suddenly increases, the heat installed in the refrigerant tank is activated to increase the heat recovered by the heat pump, so the solvent vapor level can be quickly recovered and stable cleaning can be performed. obtain.

In addition, the auxiliary heater is installed in the refrigerant tank installed in the cooling pipe system, and no heater is used in the solvent system, so unlike previous steam cleaning equipment, solids in the solvent solution may not be deposited. There is no chance of the heater burning out, and the operating rate of the equipment is greatly improved.

As mentioned above, the present invention has excellent practical utility.

[Brief explanation of drawings]

FIG. 1 is a system diagram of a heat pump type steam cleaning apparatus showing an embodiment of the present invention. Figures 2 and 3
The figure is a system diagram of a conventional heat pump type steam cleaning device. 1...Steam cleaning tank, 1a...Cleaning section, 1b...
Storage part, 2... Heat pump, 2a... Compressor,
2b... Condenser, 2c... Expansion valve, 2d... Evaporator, 3... Cooling device, 4... First cooling pipe group, 4'
...Second cooling pipe group, 6...Heat exchange tube, 7...Pump, 8...Heat exchange tube, 9...Pump, 10...Object to be cleaned, 13...Refrigerant tank, 14...First Steam level detector, 15... second steam level detector,
16...pump, 18...refrigerant outflow pipe, 22...
...Heater, 25...First steam level control mechanism, 2
6...Second steam level control mechanism, Ls...Standard solvent vapor level.

Claims (1)

[Claims] 1. A first solvent vapor disposed above the standard solvent vapor level Ls, which is the upper limit level of solvent vapor during steady operation.
A steam cleaning tank 1 that includes a cooling pipe group 4 and a second cooling pipe group 4' disposed therebelow; an evaporator 2d that cools the refrigerant flowing into the second cooling pipe group 4'; and the inside of the steam cleaning tank 1. condenser 2b that heats the solvent solution of
a heat pump 2 equipped with; a refrigerant tank 13 having a heater 22 interposed in a refrigerant outflow pipe 18 leading from the second cooling pipe group 4' to the evaporator 2d; and a refrigerant tank 13 having a heater 22; a cooling device 3;
a first steam level control mechanism 25 that detects when the solvent vapor level in the steam cleaning tank 1 rises by a predetermined amount above the standard solvent vapor level Ls and operates the cooling system using the first cooling pipe group 4; The solvent vapor level in steam cleaning tank 1 is the standard solvent vapor level.
A heat pump type steam cleaning device characterized by comprising a second steam level control mechanism 26 which detects this and operates a heater 22 when the steam level has dropped to a predetermined amount or less from Ls. 2 The first steam level control mechanism 25 operates the heat pump 2 simultaneously with the operation of the cooling system by the first cooling pipe group 4.
The heat pump steam cleaning device according to claim 1, wherein the heat pump type steam cleaning device is configured to stop or operate under partial load. 3 In the steam cleaning tank 1, a first cooling pipe group 4 arranged above the standard solvent vapor level Ls, which is the upper limit level of solvent vapor during steady operation, and a second cooling pipe group 4' arranged below it are provided. During steady operation of the device, only the cooling system by the second cooling pipe group 4' is operated, and the heat pump 2 operates the second cooling system.
When the heat of the refrigerant flowing out from the cooling pipe group 4' is recovered and the solvent liquid in the steam cleaning tank 1 is heated using the recovered heat, and the solvent vapor level rises by a predetermined amount from the standard solvent vapor level Ls. Alternatively, when the device operation is stopped, the cooling system by the first cooling pipe group 4 is operated, and the refrigerant flowing into the cooling pipe group 4 is cooled by the cooling device 3 provided separately from the heat pump 2, and the heat pump 2 is stopped or Partial load operation is performed, and when the solvent vapor level drops by a predetermined amount from the standard solvent vapor level Ls or when the device is started up, the refrigerant flowing out from the second cooling pipe group 4' is inserted into the outflow pipe 18. A method for operating a heat pump type steam cleaning apparatus, characterized in that the amount of heating of the solvent solution by the heat pump 2 is increased by supplementary heating by the heater 22 of the tank 13.