JP3286485B2 - Compression metal hydride heat pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor driven hydrogen storage type heat pump system utilizing metal hydride.

[0002]

2. Description of the Related Art FIG. 7 shows a compression type metal hydride heat pump disclosed in Japanese Patent Publication No. 3-16594. In this apparatus, a plurality of metal hydride tanks that store metal hydrides and sequentially exchange heat with a plurality of types of heat medium are sequentially operated in a hydrogen gas release operation (heat absorption operation) mode and a hydrogen gas storage operation (heat generation operation) mode. It employs a batch operation system in which the metal hydrides are alternately switched, and is provided with a heat exchanger (not shown) and has three or more metal hydride tanks MH1 to MH1 for storing metal hydrides.
MH3, a compressor 100 for compressing hydrogen gas, and a suction-side transfer conduit 104 for connecting the metal hydride tanks MH1 to MH3 and the suction side of the compressor 100 via a valve V so as to transfer hydrogen gas, respectively. A discharge side transfer pipe line 105 for connecting the metal hydride tanks MH1 to MH3 and the discharge side of the compressor 100 via a valve V so as to transfer hydrogen gas, and controlling each valve V sequentially to open and close. Metal hydride tanks MH1 to MH
3 and a control means 106 for sequentially switching the communication between one of the two pipelines 104 and 105. FIG. 8 shows the valve switching timing of this device, and FIG. 9 shows the change in the cooling output after startup. In FIG. 8, cycle 1 indicates a hydrogen releasing (endothermic) operation period of the metal hydride tank MH1, cycle 2 indicates a hydrogen releasing (endothermic) operation period of the metal hydride tank MH2, and cycle 3 indicates a metal hydride tank MH3. 3 shows a hydrogen release (endothermic) operation period of FIG.

As shown in FIG. 8, each of the metal hydride tanks MH1 to MH3 terminates the hydrogen releasing (endothermic) operation for one cycle period, pauses for 0.5 cycle period, and then stores hydrogen for one cycle period. (Heat generation) operation, and then
Pause for 0.5 cycle period. The operation modes of the metal hydride tanks MH1 to MH3 are shifted in phase by one cycle period.

[0004]

However, in the conventional apparatus described above, if the outside air temperature increases during the cooling operation, the pressure in the metal hydride storage tank increases, and it is necessary to increase the pressure resistance accordingly. is there. Further, the pressure of the metal hydride tank on the storage side is adjusted to an optimal value (for example, 10 kg / c).
If m less than ²⁾ Tosureba outside air temperature is high and reduced internal and external temperature difference absorbing side metal hydride tank is the heat transport capacity is limited to, cooling capacity is limited low for this.

On the other hand, in the heating operation, when the outside air temperature decreases, the pressure of the metal hydride tank on the discharge side decreases to a negative pressure, and there is a possibility that air may enter the apparatus from the outside. Also, if the pressure of the discharge-side metal hydride tank is maintained at a positive pressure, when the outside air temperature is low, the temperature difference between the inside and outside of the discharge-side metal hydride tank is reduced, and its heat transport capacity is limited,
This limits the heating capacity to a low level.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a compression metal hydride heat pump capable of realizing an improvement in heat transport capacity despite operating in a preferable pressure range. , Its purpose.

[0007]

According to a first aspect of the present invention, there is provided:
Three or more heat exchangers for storing metal hydrides and sequentially exchanging heat with a plurality of types of heat medium, a compressor for compressing hydrogen gas, and a low pressure discharged from the heat exchanger in a hydrogen gas release mode A low-pressure pipe for introducing hydrogen gas into the compressor through a low-pressure valve, and a high-pressure pipe for storing high-pressure hydrogen gas discharged from the compressor in the heat exchanger in a hydrogen gas storage mode via a high-pressure valve And a control means for alternately switching between the two modes of the heat exchanger by sequentially opening and closing the respective valves to alternately set a hydrogen gas storage period and a hydrogen gas release period in the heat exchangers. In the hydride heat pump, the control unit is configured to set a cooling gas pressure setting operation to set the number of the heat exchangers in the hydrogen gas storage mode to be greater than the number of the heat exchangers in the hydrogen gas release mode during a cooling operation. And at least one of a heating gas pressure setting operation of setting the number of the heat exchangers in the hydrogen gas release mode to be larger than the number of the heat exchangers in the hydrogen gas storage mode during the heating operation. A compression-type metal hydride heat pump.

[0008] In a second configuration of the present invention, in the first configuration, the control means may further include: the number of the heat exchangers in the hydrogen gas occlusion mode during the cooling operation, the heat exchanger in the hydrogen gas release mode. The number of the heat exchangers in the hydrogen gas release mode during the heating operation is set to be greater than the number of the heat exchangers in the hydrogen gas storage mode during the heating operation. And

[0009] In a third aspect of the present invention, in the first aspect, the control means may further include, during cooling, externally connecting the heat exchanger after the end of the hydrogen gas storage period and before the start of the hydrogen gas release period. A pre-cooling period for pre-cooling by the heat medium from a heat source is set. In a fourth configuration of the present invention, in the first configuration, the control unit may further include, during heating, the heat exchanger after the end of the hydrogen gas release period and before the start of the hydrogen gas storage period from an external heat source. A preheating period for preheating by the heat medium is set.

According to a fifth aspect of the present invention, in the above-mentioned first aspect, the control means may further include, during cooling, the heat exchanger mounted on the heat exchanger after the end of the hydrogen gas release period and before the start of the hydrogen gas storage period. A sensible heat recovery period for cooling the heat medium for cooling the object to be cooled is set. In a sixth configuration of the present invention, in the above-described first configuration, the control unit may further include, during heating, an object to be heated in the heat exchanger after the end of the hydrogen gas storage period and before the start of the hydrogen gas release period. A sensible heat recovery period for heating the heat medium for heating is set.

According to a seventh aspect of the present invention, in the third or fourth aspect, the control means further reduces or stops the capacity of the compressor during at least a part of the preheating or precooling period. It is characterized by having. According to an eighth aspect of the present invention, in the fifth or sixth aspect, the control means is further configured to transport the heat medium for cooling the object to be cooled during at least a part of the sensible heat recovery period. It is characterized in that the capacity of the transportation means is reduced or stopped.

[0012]

The three or more heat exchangers storing metal hydrides are sequentially connected to the low-pressure line and the high-pressure line by valves. As a result, the heat exchanger in the hydrogen gas release mode releases hydrogen to the low-pressure pipe to perform an endothermic operation, and the heat exchanger in the hydrogen gas storage mode stores hydrogen from the high-pressure pipe to perform an exothermic operation. , A cooling (cooling) operation or a heating (heating) operation is performed.

Particularly, in the first or second configuration of the present invention,
At least one of a cooling operation in which the number of storage-side heat exchangers is increased from the number of release-side heat exchangers and a heating operation in which the number of release-side heat exchangers is set to be larger than the number of storage-side heat exchangers are performed. Therefore, the following operation and effect can be obtained. That is,
If such a cooling operation is performed, the amount of hydrogen gas stored per storage-side heat exchanger is reduced by the above-mentioned additional amount, so that the temperature difference between the inside and outside of the storage-side heat exchanger and the hydrogen gas flow rate can be reduced without reducing the hydrogen gas flow rate. The pressure can be reduced. Therefore, the pressure resistance of the storage-side heat exchanger can be reduced without deteriorating the cooling capacity, and the cooling capacity can be increased by increasing the hydrogen gas flow rate by the above-mentioned additional capacity.

In addition, if such a heating operation is performed, the amount of hydrogen gas released per discharge-side heat exchanger increases by the above-mentioned additional amount, so that the discharge-side heat exchanger can be used without reducing the hydrogen gas flow rate. The temperature difference and pressure inside and outside can be increased. Therefore, it is possible to prevent the pressure of the discharge side heat exchanger from becoming negative without deteriorating the heating capacity, and it is possible to increase the heating capacity by increasing the flow rate of the hydrogen gas by the increased amount.

[0015] In a third configuration of the present invention, in the first configuration, the heat exchanger is precooled by a heat medium from an external heat source after the end of the hydrogen gas storage period and before the start of the hydrogen gas release period during cooling. Therefore, when the hydrogen gas storage mode is switched between the two heat exchangers, a decrease in the cooling output can be prevented. In the fourth configuration of the present invention, in the first configuration, the heat exchanger is further preheated by the heat medium from the external heat source after the end of the hydrogen gas release period and before the start of the hydrogen gas storage period during heating. When the hydrogen gas release mode is switched between the two heat exchangers, it is possible to prevent a decrease in the heating output.

According to a fifth aspect of the present invention, in the above-described first aspect, during cooling, the heat medium for cooling the object to be cooled is cooled by the heat exchanger after the end of the hydrogen gas release period and before the start of the hydrogen gas storage period. Since the sensible heat recovery period for cooling is set, the cooling output can be increased when the hydrogen gas release mode is switched between the two heat exchangers. In a sixth configuration of the present invention, in the first configuration, the heating medium for heating an object to be heated is further heated by the heat exchanger after the end of the hydrogen gas occlusion period and before the start of the pre-hydrogen gas release period. Since the sensible heat recovery period for heating is set, the heating output can be increased when the hydrogen gas storage mode is switched between the two heat exchangers.

According to a seventh aspect of the present invention, in the above third or fourth aspect, the control means further reduces or stops the capacity of the compressor during at least a part of the preheating or precooling period. Power can be saved as described below. According to an eighth aspect of the present invention, in the fifth or sixth aspect, further, the control means transports the heat medium for cooling the object to be cooled during at least a part of the sensible heat recovery period. Since the capacity of the means is reduced or stopped, a change in temperature of the heat medium for cooling the object to be cooled can be reduced as described later.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the apparatus of the present invention will be described with reference to the block diagram shown in FIG. 1 and the operation cycle diagram shown in FIG.
Numerals 1a, 1b and 1c denote tank-shaped heat exchangers for storing metal hydrides, respectively, and 2 a compressor, 3a, 3b and 3
c is a low-pressure valve, 4a, 4b, and 4c are high-pressure valves, 5 is a high-pressure pipe, 6 is a low-pressure pipe, 70, 72, and 74 are outside air as an external heat medium and indoor air (room air) as a heat medium for air conditioning. , 71, each of which is separately introduced into the heat exchangers 1a, 1b, 1c.
73 and 75 are ducts for individually discharging outside air as an external heat medium and inside air as a heat medium for air conditioning from the heat exchangers 1a, 1b, 1c, 76 is a duct for introducing outside air, 77 is a duct for discharging outside air, 78 is a duct for introducing inside air to a damper 8 described later, 79 is a duct for sending inside air to a room, 8
Is a film that switches the connection between the ducts 70, 72, 74 and the ducts 76, 78 and also controls the opening degree, and switches the connection between the ducts 71, 73, 75 and the ducts 77, 79 and also controls the opening degree. Screen damper (hereinafter abbreviated as damper), 9 is a controller, 11
Is a fan for introducing outside air, and 12 is a fan for introducing inside air.

The heat exchangers 1a, 1b, 1c are provided with valves 3a, 3a
By opening b and 3c, hydrogen gas is individually discharged to the low pressure line 6, and by opening the valves 4a, 4b and 4c, hydrogen gas is individually absorbed from the high pressure line 5. The damper 8 has a film screen that is moved by a motor. When the screen is moved and a predetermined window opened in the screen is aligned with the openings of the ducts 70 to 79, the outside air introduced into the heat exchangers 1a, 1b, 1c and The destination of the combination of inside air and the outside air and inside air sent from the heat exchangers 1a, 1b, 1c is easily determined.

9 is a controller with a built-in microcomputer.
Compressor 2, valves 3a, 3b, 3c, valves 4a, 4b, 4c,
The control of the damper 8 and the fans 11 and 12 is performed. The compressor 2 is driven by a driving means (not shown) such as a motor to compress the hydrogen gas, and the heat exchangers 1a, 1b, 1c open and close the valves 3a, 3b, 3c, 4a, 4b, 4c to supply the hydrogen gas. Performs occlusion and release. The metal hydride stored in the heat exchangers 1a, 1b, 1c is LaNi ₅ .MmN
i ₅ (Mm is Mitsushumetaru), and the like FeTi. These metal hydrides are well known to absorb heat by a dehydrogenation reaction and generate heat by a hydrogenation reaction. The cold and warm heat generated by the occlusion and release of the heat exchangers 1a, 1b and 1c is transmitted to the inside air or the outside air.

Hereinafter, the cooling operation of the apparatus will be described. However, in order to simplify the explanation, the controller 9
The valves 3a, 3b, 3c, 4 are periodically arranged as shown in FIG.
a, 4b, and 4c are opened and closed, and the compressor 2 is driven at a predetermined rotation speed. This apparatus is implemented by sequentially repeating a phase period (also simply referred to as a cycle) 10, 20, 30 which is set to an equal fixed period. The cycle 10 is a period in which the heat exchanger 1a emits hydrogen gas in principle and the other heat exchangers 1b and 1c store hydrogen gas in principle, and the cycle 20 is a cycle in which the heat exchanger 1b emits hydrogen gas in principle. Done, other heat exchanger 1
a and 1c are periods in which hydrogen gas is stored in principle,
The cycle 30 is a period in which the heat exchanger 1c emits hydrogen gas in principle, and the other heat exchangers 1a and 1b absorb hydrogen gas in principle. The cycle 10 is sequentially divided into a sensible heat recovery period t1, a main period t2, and a precooling period t3, the cycle 20 is sequentially divided into a sensible heat recovery period t4, a main period t5, and a precooling period t6, and the cycle 30 is sequentially divided into a sensible heat recovery period t4, a precooling period t6. It is divided into a heat recovery period t7, a main period t8, and a pre-cooling period t9.

Hereinafter, the operation will be described in order from the period t2. At t2, the valve 3a is opened, the valves 3b and 3c are closed, and the valve 4a
Is closed, the valves 4b and 4c are opened, the inside air is introduced into the heat exchanger 1a, and the outside air is introduced into the heat exchangers 1b and 1c. As a result, the heat exchanger 1a absorbs heat from the inside air, and the heat exchanger 1a
b and 1c exhaust heat to the outside air.

At t3, the valve 4b is closed. Thereby, the heat exchanger 1b is pre-cooled to near the outside air temperature. t4
Then, the valve 3b is opened, the valves 3a and 3c are closed, the valves 4a and 4b are closed, the valve 4c is opened, the inside air is introduced into the heat exchangers 1a and 1b, and the outside air is introduced into the heat exchanger 1c. . This allows
The heat exchangers 1a and 1b absorb heat, and the heat exchanger 1c exhausts heat. Since both the valves 3a and 4a are closed, the heat exchanger 1a converts a considerable part of the sensible heat (temperature difference between the air and the internal air × specific heat × mass of the heat exchanger 1a) stored in its own heat capacity into the internal air. give.

At t5, the valve 4a is opened, and the heat exchanger 1a, whose temperature has risen to about the inside air temperature, stores hydrogen gas.
At t6, the valve 4c is closed. Thereby, the heat exchanger 1c is pre-cooled to near the outside air temperature. At t7, the valve 3c
Is open, the valves 3a and 3b are closed, the valves 4b and 4c are closed, the valve 4a is open, inside air is introduced into the heat exchangers 1b and 1c, and outside air is introduced into the heat exchanger 1a. Thereby, the heat exchanger 1
b and 1c absorb heat, and the heat exchanger 1a exhausts heat. Valve 3b,
Since both of the heat exchangers 4b are closed, the heat exchanger 1b gives a considerable portion of the sensible heat stored in its heat capacity to the inside air.

At t8, the valve 4b is opened, and the heat exchanger 1b, whose temperature has increased to about the inside air temperature, stores hydrogen gas.
At t9, the valve 4a is closed. Thereby, the heat exchanger 1a is pre-cooled to near the outside air temperature. At the next t1, the valve 3a is open, the valves 3b and 3c are closed, the valves 4a and 4c are closed, and the valve 4 is closed.
b is open, inside air is introduced into the heat exchangers 1a and 1c, and outside air is introduced into the heat exchanger 1b. Thereby, the heat exchangers 1a and 1c absorb heat, and the heat exchanger 1b performs exhaust heat. Valve 3
Since both c and 4c are closed, the heat exchanger 1c gives a considerable portion of the sensible heat stored in its own heat capacity to the inside air.

In the above embodiment, the cooling operation has been described, but the principle of the heating operation is the same. In the timing chart of FIG. 2, after the discharge operation and the occlusion operation are switched, the heat exchanger performing the discharge operation and t1, t4, t7 period (preheating period)
The outside air may be supplied to the heat exchanger that does not exchange hydrogen gas, and the inside air may be supplied to the heat exchanger that performs the occlusion operation and the heat exchanger that does not exchange hydrogen gas during t3, t6, and t9 (sensible heat recovery period).

(Embodiment 2) Another embodiment will be described with reference to FIG.
An operation during cooling will be described as an example. This example is
Ducts 71, 73, 75 of each heat exchanger 1a, 1b, 1c
Temperature sensors 91 to 93 are individually arranged, and the sensible heat recovery periods t1, t4, t7 described in the first embodiment.
(In other words, the start of the main periods t2, t5, t8)
Is determined on the basis of the temperature of the temperature sensors 91 to 93, and more specifically, the temperature of the inside air derived from the heat exchanger during the sensible heat recovery operation.

More specifically, the controller 9 comprises:
At present, it is checked whether the period is the sensible heat recovery period t1, t4, or t7. If the sensible heat recovery period is t1, whether the temperature of the inside air sent from the heat exchanger 1c exceeds a predetermined threshold temperature Tt1. The sensible heat recovery period t1 is terminated. Next, if the present time is the sensible heat recovery period t4, it is checked whether or not the temperature of the inside air sent from the heat exchanger 1a exceeds a predetermined threshold temperature Tt1, and if it exceeds, the sensible heat recovery period t4 ends. Next, if the present time is the sensible heat recovery period t7, it is checked whether or not the temperature of the inside air sent from the heat exchanger 1b exceeds a predetermined threshold temperature Tt1, and if it exceeds, the sensible heat recovery period t7 ends. The threshold temperature Tt1 is a predetermined temperature (for example, about 5 degrees Celsius) lower than the inside air temperature.

At the time of heating, in the above temperature comparison, it is checked whether or not the temperature of the inside air sent from the heat exchanger during the recovery of the sensible heat is lower than a predetermined threshold temperature Tt2. The period may be ended. In this way, the sensible heat recovery can be sufficiently performed without uselessly extending the sensible heat recovery period.

(Embodiment 3) Another embodiment will be described with reference to FIG.
An operation during cooling will be described as an example. This example is
In the pre-cooling periods t3, t6, and t9 described in the first embodiment, the hydrogen gas occlusion and the hydrogen gas release of the heat exchangers other than the heat exchanger during the pre-cooling are also stopped similarly to the heat exchanger during the pre-cooling.

More specifically, the compressor 2 is stopped during the precooling period t3, and the valves 3a, 3b, 3c and 4a, 4a,
b and 4c are closed. With this configuration, as described above, the heat exchanger 1b is sensibly cooled (pre-cooled) from the storage temperature to the vicinity of the inside air temperature, and the heat exchanger 1a performs sensible heat recovery during the pre-cooling period t3, thereby exchanging heat. The vessel 1c performs sensible heat cooling to be cooled to a temperature near the outside air temperature.

Similarly, the compressor 2 is stopped during the pre-cooling period t6, the valves 3a, 3b, 3c and 4a, 4b, 4c are closed, and the compressor 2 is stopped during the pre-cooling period t9, and the valves 3a,
Closing 3b, 3c and 4a, 4b, 4c has the same effect. By doing so, the periods t3, t
6. Since the compressor can be stopped at t9, the power for the compressor can be reduced.

The operation during the heating operation is the same as above,
In FIG. 2, the operation of releasing hydrogen gas and the operation of storing hydrogen gas may be reversed. Embodiment 4 Another embodiment will be described with reference to FIG. In this embodiment, in the sensible heat recovery periods t1, t4, and t7 described in the first embodiment, the sensible heat cooling operation (the operation of cooling the temperature of the heat exchanger from the pre-cooled heat exchanger temperature to the hydrogen gas release temperature). To reduce (or stop) the inside air flow rate of the heat exchanger that performs the above.

More specifically, the inside air flow introduced into the heat exchanger 1b during the sensible heat recovery period t4, the inside air flow introduced into the heat exchanger 1c during the sensible heat recovery period t7, and the heat exchanger during the sensible heat recovery period t1 The inside air flow introduced into 1a is set to 0 or partially reduced by controlling the damper 8, respectively. With this configuration, the temperature of the heat exchanger during the sensible heat cooling operation due to the release of hydrogen gas can be rapidly reduced to the hydrogen gas release temperature, and normal inside air cooling can be started early. In addition, the inside air that does not reach the hydrogen gas release temperature and is still not sufficiently cooled from the heat exchanger that is still high based on the hydrogen gas release temperature is not sent into the room, and the cooling feeling can be improved. .

The operation during the heating operation is the same as above, and the operation of releasing the hydrogen gas and the operation of storing the hydrogen gas in FIG. 2 may be reversed. FIG. 4 shows the time change of the cooling output of the device of the first embodiment, FIG. 5 shows the time change of the cooling output of the device of the second embodiment, and FIG. 6 shows the time change of the cooling output of the device of the third embodiment.
FIG. 9 shows the change over time of the cooling output of the conventional apparatus shown in FIG. However, the structure of each device and the operating conditions other than those described above are the same. From these figures, it can be seen that the devices of Examples 1 to 3 have smaller fluctuations in the cooling output than the conventional devices.

In each of the above embodiments, the number of heat exchangers may be four or more, and the heat medium and its transport piping system may be those used in ordinary air conditioning or refrigeration or heat pump devices. What you can do is obvious. Further, since the control of the valves 3a, 3b, 3c, 4a, 4b, 4c, the compressor 2, and the damper 8 by the controller based on the time or the detected temperature is extremely simple, the flowchart or the control circuit diagram is omitted.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the apparatus of the present invention.

FIG. 2 is an operation cycle diagram of the device of FIG. 1;

FIG. 3 is a block diagram illustrating an apparatus according to a second embodiment.

FIG. 4 is a diagram illustrating a change over time of a cooling output of the apparatus according to the first embodiment.

FIG. 5 is a diagram illustrating a change over time of a cooling output of the apparatus according to the second embodiment.

FIG. 6 is a diagram illustrating a change over time of a cooling output of the apparatus according to the third embodiment.

FIG. 7 is a block diagram showing a conventional device.

8 is an operation cycle diagram of the device of FIG.

FIG. 9 is a diagram showing a change over time of a cooling output of the apparatus of FIG. 7;

[Explanation of symbols]

1a, 1b, 1c are heat exchangers, 2 is a compressor, 3a, 3
b, 3c are low-pressure valves, 4a, 4b, 4c are high-pressure valves, 5 is a high-pressure pipe, 6 is a low-pressure pipe, 70 to 79 are ducts, 8 is a damper, 9 is a controller (control means), and 11 and 12 are Fan (heat medium transport means).

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayoshi Miura 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (72) Inventor Nobuo Fujita 1-Toyota-cho, Toyota-shi, Aichi Prefecture Toyota Motor Vehicle Stock Inside the company (72) Inventor Hiroshi Aoki 41-41, Chuchu-ji, Yoji, Nagakute-cho, Aichi-gun, Aichi Prefecture Inside Toyota Central R & D Laboratories Co., Ltd. (56) References JP-A-63-108168 (JP, A) JP-A-6-257884 (JP, A) JP-A-7-55284 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F25B 17/12

Claims (8)

(57) [Claims] 1. A heat exchanger for storing hydrogenated metal and sequentially exchanging heat with a plurality of types of heat medium, a compressor for compressing hydrogen gas, and the heat exchanger in a hydrogen gas release mode. A low-pressure pipe for introducing the low-pressure hydrogen gas discharged from the compressor to the compressor through a low-pressure valve, and the high-pressure hydrogen gas discharged from the compressor to the heat exchanger in a hydrogen gas storage mode through a high-pressure valve. A high-pressure pipe to be occluded, and control means for alternately switching the two modes of the heat exchanger by sequentially opening and closing the respective valves to alternately set a hydrogen gas occlusion period and a hydrogen gas release period to the heat exchangers. A compression type metal hydride heat pump comprising: a cooling system for setting the number of the heat exchangers in the hydrogen gas storage mode to be larger than the number of the heat exchangers in the hydrogen gas release mode during a cooling operation. And at least one of a heating control operation for setting the number of the heat exchangers in the hydrogen gas release mode to be larger than the number of the heat exchangers in the hydrogen gas storage mode during the heating operation. A compression type metal hydride heat pump characterized by the above-mentioned. The control means sets the number of the heat exchangers in the hydrogen gas storage mode during the cooling operation to be greater than the number of the heat exchangers in the hydrogen gas release mode, and controls the number of the heat exchangers during the heating operation. 2. The compression metal hydride heat pump according to claim 1, wherein the number of the heat exchangers in the hydrogen gas release mode is set to be larger than the number of the heat exchangers in the hydrogen gas storage mode. 3. The cooling means sets a pre-cooling period in which the heat exchanger is pre-cooled by the heat medium from an external heat source after the end of the hydrogen gas storage period and before the start of the hydrogen gas release period during cooling. The compression metal hydride heat pump according to claim 1, wherein 4. The heating device according to claim 1, wherein said control means sets a preheating period in which the heat exchanger is preheated by the heat medium from an external heat source after the end of the hydrogen gas release period and before the start of the hydrogen gas storage period during heating. The compression metal hydride heat pump according to claim 1, wherein 5. The sensible heat recovery period for cooling the heat medium for cooling the object to be cooled by the heat exchanger after the end of the hydrogen gas release period and before the start of the hydrogen gas storage period during cooling. The compression type metal hydride heat pump according to claim 1, wherein 6. The sensible heat recovery period in which the heating means heats the heating medium for heating the object to be heated by the heat exchanger after the end of the hydrogen gas storage period and before the start of the hydrogen gas release period during heating. The compression type metal hydride heat pump according to claim 1, wherein 7. The compression metal hydride heat pump according to claim 3, wherein the control means reduces or stops the capacity of the compressor during at least a part of the preheating or precooling period. 8. The control means reduces or stops the ability of the heat medium transport means for transporting the heat medium for cooling the object to be cooled during at least a part of the sensible heat recovery period. 7. The compression metal hydride heat pump according to 5 or 6.