Patent Publication Number: US-2004052665-A1

Title: Double-acting refrigerant compressor

Description:
TECHNICAL FIELD  
       [0001] This invention relates to a reciprocating refrigerant compressor used as a refrigerant compressor for an automotive air conditioner, and more particularly to a reciprocating refrigerant compressor of a type in which pistons reciprocate, such as a wobble plate compressor and a swash plate compressor.  
       BACKGROUND ART  
       [0002] A wobble plate compressor includes a cylinder block having a plurality of cylinder bores, a plurality of pistons for reciprocating within the respective cylinder bores, a cylinder head secured to an end face of the cylinder block via a valve plate, and a plurality of inlet valves for opening and closing a plurality of inlet ports formed through the valve plate.  
       [0003] Within the cylinders are formed compression chambers, respectively, and the volume of each compression chamber varies with the motion of a piston associated therewith.  
       [0004] The cylinder head has a suction chamber formed therein for receiving low-pressure refrigerant gas flowing therein from an evaporator side.  
       [0005] The number of the inlet valves and the number of the inlet ports form d through th valve plate are equal to the number of the cylinder bores, similarly to the number of the compression chambers and the number of the pistons.  
       [0006] The suction chamber communicates with the compression chambers via the inlet ports.  
       [0007] During the suction stroke, as the volume of a compression chamber progressively increases, the inlet valve is bent toward the compression chamber side to open the inlet port, via which refrigerant gas in the suction chamber is drawn into the compression chamber.  
       [0008]FIG. 13 is a fragmentary enlarged plan view of a valve plate of a conventional wobble plate compressor.  
       [0009] A valve plate  302  is formed with inlet ports  315 , and outlet ports  316  are formed inward of the inlet ports  315  (radially inward in the valve plate  302 ). Further, the inlet ports  315  and the outlet ports  316  are located inward of respective opening edges  306   a  of the cylinder bores. An inlet valve  321  is formed with a hole  363 , such that the outlet port  316  is prevented from being closed by the inlet valve  321 .  
       [0010] The opening edge  306   a  of the cylinder bore is formed with a stopper recess  370  at a location opposed to a protuberance  321   d  of the inlet valve  321 .  
       [0011] As the piston moves toward the bottom dead center position during the suction stroke, the difference in pressure between the compression chamber and the suction chamber is increased, whereby the inlet valve  321  is bent toward the compression chamber side to open the inlet port  315 , via which refrigerant gas in the suction chamber is drawn into the compression chamber. At this time, the protuberance  321   d  of the inlet valve  321  abuts on the stopper recess  370 , which limits the bend of th inlet valve  321 .  
       [0012] The dimension of depth of the stopper recess  370  (length from an end face of the cylinder block to the bottom surface of the stopper recess  370 ) is configured to be small to thereby reduce the suction pulsation.  
       [0013] As the piston moves toward the top dead center position during the compression stroke, the volume of the compression chamber is progressively reduced to increase the pressure in the compression chamber. At this time, the inlet valve  321  is brought into intimate contact with the valve plate  302  by high pressure to close the inlet port  315 .  
       [0014] However, if the dimension of depth of the stopper recess  370  is small, the suction efficiency is lowered, which degrades the performance of the refrigerant compressor.  
       [0015] To improve the performance of the refrigerant compressor, it is necessary to increase the area of an opening formed during suction of refrigerant. To meet this requirement, it is necessary to increase the area of the inlet port  315 . If the area of the inlet port  315  is increased, it is necessary to enlarge the inlet valve  321  accordingly.  
       [0016]FIG. 14 is a perspective view showing a valve plate and a valve sheet proposed by the present inventors. FIG. 15 is a plan view of the valve plate shown in FIG. 14. FIG. 16 is a partial view of an end face of a cylinder block and the valve sheet as viewed from the valve sheet side. FIG. 17 is a cross-sectional view tak n on line XVII-XVII of FIG. 16, in which FIG. 17( a ) is a view showing a state befor an inlet valve is opened, and FIG. 17( b ) is a view showing a state after the inlet valve is opened. FIG. 18 is a fragmentary enlarged perspective view of the cylinder block.  
       [0017] As shown in FIG. 14, the inlet port  15  and the inlet valve  421  are larger than the inlet port  315  and the inlet valve  321 , respectively.  
       [0018] The inlet port  15  bulges out arcuately along the opening edge  406   a  of the cylinder bore  406 . In the same manner as the inlet port  15 , a port-blocking portion  421   a  of the inlet valve  421  bulges out arcuately along the opening edge  406   a.    
       [0019] This wobble plate compressor has features in common with the wobble plate compressor shown in FIG. 13 in that the outlet port  16  is formed inward of the inlet port  15 , that the inlet valve  421  is formed with the hole  463 , and that the cylinder block  401  is formed with the stopper recess  470  opposed to the protuberance  421   d  of the inlet valve  421 .  
       [0020] If the area of the inlet port  15  is increased, the amount of refrigerant gas flowing into the compression chamber  460  during high-load operation is increased, so that the opposite ends of the port-blocking portion  421   a  of the inlet valve  421  is largely bent into the compression chamber  460  (see FIG. 17( b )), which causes excessively large twisting load to act on root portions  421   c ,  421   d  of the inlet valve  421 .  
       [0021] This results in the problem of deformation or breakage of the inlet valve  421 , and low-pressure pulsation.  
       [0022] It is an object of the invention to provide a reciprocating refrigerant compressor that is capable of preventing deformation and breakage of inlet valves and low-pressure pulsation, which might occur when the areas of the inlet ports are increased.  
       DISCLOSURE OF THE INVENTION  
       [0023] To attain the above object, a reciprocating refrigerant compressor according the present invention includes a cylinder block having a plurality of cylinder bores formed therein, a cylinder head secured to an end face of the cylinder block via a valve plate, a low-pressure chamber formed within the cylinder head, a plurality of inlet ports formed through the valve plate, for communicating between the low-pressure chamber and the cylinder bores, and a plurality of inlet valves for opening and closing the inlet ports, the inlet valves each having an inlet port-blocking portion formed to have a generally arcuate shape, wherein a main stopper recess is formed at an opening edge of each cylinder bore of the cylinder block, for supporting, during an suction stroke, a central protuberance formed in a central portion of the inlet port-blocking portion of the inlet valve with respect to a direction along an arc of the inlet port-blocking portion in a manner protruding outward in a radial direction of the cylinder bore, and a plurality of sub-stopper recesses are formed at the opening edge of each cylinder bore of the cylinder block, for supporting, during the suction stroke, side protuberances, respectively, which are formed at opposite ends of the inlet port-blocking portion of the inlet valve with respect to the direction along the arc of the inl t port-blocking portion in a manner protruding outward in a radial direction of the cylinder bore.  
       [0024] Even when the area of the inlet port is increased, not large twisting motion is applied to the inlet valve during the suction stroke, and vibrations of the inlet valve are prevented, which makes it possible to prevent deformation and breakage of the inlet valve and low-pressure pulsation.  
       [0025] Preferably, bottom surfaces of the sub-stopper recesses are sloped.  
       [0026] When the inlet valve is bent toward the compression chamber side during the suction stroke, the side protuberances come into collision with the sub-stopper recesses. However, at this time, the side protuberances are brought into surface contact with the bottom surfaces of the sub-stopper recesses, which lessens the impact of the collision and suppresses noise. Further, when the inlet port is bent, the inlet port-blocking portion is largely bowed inward at the approximately central portion thereof, which makes it easier to draw in refrigerant gas, thereby further enhancing the suction efficiency.  
       [0027] Preferably, depth of the sub-stopper recesses is made larger than depth of the main stopper recess.  
       [0028] When the inlet valve is bent toward the compression chamber side during the suction stroke, first, the central protuberance comes into collision with the main stopper recess, thereby being restricted in lift thereof, and then the side protuberances come into collision with the sub-stopp r recess s, thereby being restricted in lift thereof. Thus, the timing in which the lift of th side protuberances is restricted is d layed relative to the timing in which the lift of the central protuberance is restricted, which makes it easy to draw in refrigerant.  
       [0029] Preferably, bottom surfaces of the sub-stopper recesses are sloped, and depth of the sub-stopper recesses is made larger than depth of the main stopper recess.  
       [0030] Preferably, depth of the sub-stopper recesses is made smaller than depth of the main stopper recess.  
       [0031] When the inlet valve is bent toward the compression chamber side during the suction stroke, first, the side protuberances come into collision with the sub-stopper recesses, thereby being restricted in lift thereof, and then the central protuberance comes into collision with the main stopper recess, thereby being restricted in lift thereof. Thus, the lift of the side protuberances is restricted before the lift of the central protuberance is restricted, which prevents vibrations of the inlet valves more positively.  
       [0032] Preferably, bottom surfaces of the sub-stopper recesses are sloped, and depth of the sub-stopper recesses is made smaller than depth of the main stopper recess. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0033]FIG. 1 is a partial view of an end face of a cylinder block and a valve sheet of a wobble plate compressor according to a first embodiment of the present invention, as viewed from the valve sheet side;  
     [0034]FIG. 2 is a cross-sectional view taken on line II-II of FIG. 1, in which FIG. 2( a ) is a view showing a state before an inlet valve is opened, and FIG. 2( b ) is a view showing a state after the inlet valve is opened;  
     [0035]FIG. 3 is a perspective view showing the whole of the valve plate and the valve sheet;  
     [0036]FIG. 4 is a plan view showing the whole of the valve plate;  
     [0037]FIG. 5 is a fragmentary enlarged perspective view of the cylinder block of the wobble plate compressor according to the first embodiment of the present invention;  
     [0038]FIG. 6 is a cross-sectional view showing the wobble plate compressor according to the first embodiment of the present invention;  
     [0039]FIG. 7 is a fragmentary enlarged perspective view of a cylinder block of a wobble plate compressor according to a second embodiment of the present invention;  
     [0040]FIG. 8 is a fragmentary enlarged cross-sectional view useful for explaining the relationship between an inlet valve and protuberances of the cylinder block, in which FIG. 8( a ) is a view showing a state before the inlet valve is opened, and FIG. 8( b ) is a view showing a state after the inlet valve is opened;  
     [0041]FIG. 9 is a cross-sectional view of the inlet valve after it is opened, as viewed from a different angle;  
     [0042]FIG. 10 is a fragmentary enlarged perspective view of a cylinder block of a wobble plate compressor according to a third embodiment of the present invention;  
     [0043]FIG. 11 is a fragmentary enlarged cross-sectional view useful for explaining the relationship between an inlet valve and protuberances of the cylinder block, in which FIG. 11( a ) is a view showing a state before the inlet valve is opened, and FIG. 11( b ) is a view showing a state after the inlet valv is op ned;  
     [0044]FIG. 12 is a cross-s ctional view of the inlet valve after it is opened, as viewed from a different angle;  
     [0045]FIG. 13 is a fragmentary enlarged plan view of a valve plate of a conventional wobble plate compressor;  
     [0046]FIG. 14 is a perspective view showing a valve plate and a valve sheet proposed by the present inventors;  
     [0047]FIG. 15 is a plan view of the valve plate shown in FIG. 14;  
     [0048]FIG. 16 is a partial view of an end face of a cylinder block and the valve sheet as viewed from the valve sheet side;  
     [0049]FIG. 17 is a cross-sectional view taken on line XVII-XVII of FIG. 16, in which FIG. 17( a ) is a view showing a state before an inlet valve is opened, and FIG. 17( b ) is a view showing a state after the inlet valve is opened; and  
     [0050]FIG. 18 is a fragmentary enlarged perspective view of the cylinder block. 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION  
     [0051] The invention will now be described in detail with reference to drawings showing preferred embodiments thereof.  
     [0052]FIG. 6 is a cross-sectional view showing a wobble plate compressor according to a first embodiment of the present invention. FIG. 1 is a partial view of an end face of a cylinder block and a valve sheet of the wobble plate compressor, as viewed from the valve sheet side. FIG. 2 is a cross-sectional view taken on line II-II of FIG. 1, in which FIG. 2( a ) is a view showing a state before an inlet valve is op ned, and FIG. 2( b ) is a view showing a state after the inlet valve is op ned. FIG. 3 is a perspective view showing th whole of the valve plate and the valve sheet. FIG. 4 is a plan view showing the whole of the valve plate, and FIG. 5 is a fragmentary enlarged perspective view of the cylinder block.  
     [0053] This compressor has a cylinder block  1  having one end thereof secured to a rear head (cylinder head)  3  via a valve plate  2  and the other end thereof secured to a front head  4 .  
     [0054] The cylinder block  1  has a plurality of cylinder bores  6  axially extending therethrough at predetermined circumferential intervals about the shaft  5 . Each cylinder bore  6  has a piston  7  slidably received therein. The cylinder bore  6  defines a compression chamber  60  therein, the volume of which is changed with motion of the piston  7 . An opening edge (cylinder bore opening edge)  6   a  of the cylinder bore  6  is formed with a main stopper recess  70  and sub-stopper recesses  71 ,  72 , as shown in FIG. 1. The stopper recesses  70 ,  71 ,  72  limit the amount of bend (opening degree) of the inlet valve  21 .  
     [0055] Within the front head  4 , there is formed a crankcase  8  within which a wobble plate  10  is accommodated for wobbling motion performed about a hinge ball  9  in a manner interlocked with the shaft  5 .  
     [0056] Within the rear head  3 , there are formed a discharge chamber  12  and a suction chamber  13  located around the discharge chamber  12 .  
     [0057] The valve plate  2  is formed with a plurality of outlet ports  16  for communicating between the cylinder bores  6  and the discharge chamber  12 , and a plurality of inlet ports  15  for communicating between the cylinder bore  6  and the suction chamber  13 , at predetermined circumfer ntial intervals. The outlet ports  16  ar opened and closed by the outlet valves  17 , and the outlet valves  17  are fixed to the rear head-side end face of the valve plate  2  together with a valve retainer  18  by a rivet  19 . Further, inlet ports  15  are opened and closed by the inlet valves  21 , and the inlet valves  21  are disposed between the valve plate  2  and the cylinder block  1 . The discharge chamber  12  and the crankcase  8  are communicated with each other via a passage  79  and an orifice  80 .  
     [0058] The respective numbers of the inlet valves  21 , the outlet valves  17 , the inlet ports  15 , the outlet ports  16 , and the compression chambers  60  are equal to the number ( 5  in this embodiment) of the cylinder bores  6 .  
     [0059] As shown in FIGS.  1  to  3 , the inlet port  15  and the outlet port  16  are located, inward of the opening edge  6   a  of the cylinder bore  6 . Further, the inlet ports  15  are located outward of the outlet ports  16  (radially outward in the valve plate  2 ). The five inlet ports  15  each largely bulge out from support centers C 1 , C 2  (see FIG. 1), and accordingly, an inlet port-blocking portion  21   a  of the inlet valve  21  is larger than an inlet port-blocking portion  321   a  of the inlet valve  321  of the prior art. It should be noted that the support center C 1  is defined as a straight line connecting between a supported point of the central protuberance  21   d  and a supported point of a root portion  21   b , and the support center C 2  is defined as a straight line connecting between the supported point of the central protuberance  21   d  and a supported point of a root portion  21   c.    
     [0060] As shown is FIG. 3, the five inlet valves  21  are int grally formed with a valve she t  62 . Each inlet valve  21  is formed with a hole  63 , which pr vents the outlet port  16  from being closed by the inlet valve  21 . Each inlet valve  21  is comprised of three protuberances  21   d ,  21   e ,  21   f , one inlet port-blocking portion  21   a , and two root portions  21   b ,  21   c . The inlet port-blocking portion  21   a  of the inlet valve  21  is formed to have a generally arcuate shape in a manner adapted to the shape of the inlet port  15 . The central protuberance  21   d  is provided in a central portion of the inlet port-blocking portion  21   a  with respect to a direction of the arc thereof, and the side protuberances  21   e ,  21   f  are provided at opposite ends of the inlet port-blocking portion  21   a  with respect to the direction of the arc of the same. The protuberances  21   d ,  21   e ,  21   f  are each protruded radially outward from the opening edge  6   a  of the cylinder bore  6  such that the central protuberance  21   d  is opposed to the main stopper recess  70  in the direction of the central axis of the cylinder bore  6 , while the side protuberances  21   e ,  21   f  are opposed to the sub-stopper recesses  71 ,  72  in the direction of the central axis of the cylinder bore  6 . The side protuberances  21   e ,  21   f  are located outward of the support centers C 1 , C 2 . The two root portions  21   b ,  21   c  support the inlet port-blocking portion  21   a.    
     [0061] The cylinder block  1  is formed with a communication passage  31  communicating between the suction chamber  13  and the crankcase  8 , and a pressure control valve  32  is arranged across an intermediate portion of the communication passage  31 , for control of pressure in the suction chamber  13  and pressure in the crankcase  8 .  
     [0062] Further, the front-side end of the shaft  5  is rotatably supported by a radial bearing  26  arranged in th front head  4 , and the rear-sid end of the shaft  5  is rotatably supported by a radial bearing  24  and a thrust bearing  25 . The shaft  5  has a thrust flange  40  fixed thereon, and a drive hub  41  mounted thereon via a hinge ball  9  which is axially slidable. The thrust flange  40  is supported on the inner wall of the front head  4  via a thrust bearing  33 . A portion of the thrust flange  40  and a portion of the drive hub  41  are connected by a linkage  42  via which the rotation of the shaft  5  is transmitted from the thrust flange  40  to the drive hub  41 . The wobble plate  10  is relatively rotatably mounted on the drive hub  41  via a radial bearing  27  and a thrust bearing  28 . The wobble plate  10  is connected to the pistons via connecting rods  11 .  
     [0063] Between the hinge ball  9  and a boss  40   b  of the thrust flange  40 , a coil spring  44  is interposed as a destroke spring, and the hinge ball  9  is urged toward the cylinder block  1  by the coil spring  44 .  
     [0064] Further, a fixed washer  45  is fixedly fitted on the shaft  5  at a location toward the cylinder block side, and between the fixed wash  45  and the hinge ball  9 , a plurality of curved springs  46  and a coil spring  47  as destroke springs are interposed in series, for urging the hinge ball  9  toward the thrust flange  40 .  
     [0065] Next, the operation of this wobble plate compressor will be described.  
     [0066] As torque of an engine, not shown, installed on a vehicle, not shown, is transmitted to the shaft  5 , the thrust flange  40  and the drive hub  41  rotate together with the shaft  5 , which causes the wobble plate  10  to wobble about the hinge ball  9 . The wobbling motion is transmitted to th pistons  7  via the connecting rods  11 , whereby the wobbling motion is converted into the linear reciprocating motion of each piston  7 . As the piston  7  reciprocates in the cylinder bore  6 , the volume of the compression chamber  60  changes, which sequentially causes the suction, compression, and delivery of refrigerant gas, whereby high-pressure refrigerant gas is delivered in an amount corresponding to an angle of inclination of the wobble plate  10 .  
     [0067] When thermal load on the compressor decreases and the pressure control valve  32  closes the communication passage  31  to increase the pressure in the crankcase  8 , the angle of inclination of the wobble plate  10  becomes smaller, so that the length of stroke of the piston  7  is decreased to reduce the displacement of the compressor. On the other hand, when thermal load on the compressor increases and the pressure control valve  32  opens the communication passage  31  to reduce the pressure in the crankcase  8 , the angle of inclination of the wobble plate  10  becomes larger, whereby the length of stroke of the piston  7  is increased to increase the displacement of the compressor.  
     [0068] In the suction stroke, as the piston  7  moves to the bottom dead center position, the difference between pressure in the compression chamber  60  and pressure in the suction chamber  13  is increased, so that the inlet valve  21  is bent into the compression chamber  60  to open the inlet port  15 , via which the refrigerant gas in the suction chamber  13  is drawn into the compression chamber  60 . As described above, each of the five inlet ports  15  largely bulges out from the support centers C 1 , C 2 , and the area thereof is larger than the area of the inl t port  315  of the prior art, which makes the suction efficiency higher than the prior art.  
     [0069] When the inlet valve  21  is bent into the compression chamber  60 , as shown in FIG. 2( b ), the central protuberance  21   d  is supported by the main stopper recess  70 , and the side protuberances  21   e ,  21   f  are supported by the sub-stopper recesses  71 ,  72 . This prevents large twisting load from being applied to the inlet valve  21 , and the inlet valve  21  from performing vibrations (so-called flapping).  
     [0070] Further, in the compression stroke, as the piston  7  moves to the top dead center position, the volume of the compression chamber  60  is progressively reduced to increase the pressure in the compression chamber  60 . At this time, the inlet valve  21  keeps the inlet port  15  closed and the outlet port  17  keeps the outlet port  16  closed. In the delivery stroke, the volume of the compression chamber  60  becomes minimum, and the pressure in the compression chamber  60  becomes maximum. When there is produced a predetermined differential pressure between the compression chamber  60  and the discharge chamber  12 , the outlet valve  17  is bent into the discharge chamber  60  to open the outlet port  16 . At this time, the inlet valve  21  keeps the inlet port  15  closed.  
     [0071] According to the first embodiment, even when the area of the inlet port  15  is increased, large twisting motion is not applied to the inlet valve  21  during the suction stroke, and vibrations of the inlet valve  21  are prevented, which makes it possible to prevent deformation and breakage of the inlet valve  21  and low-pressure pulsation.  
     [0072]FIG. 7 is a fragmentary enlarged perspective view of a cylinder block of a wobble plat compressor according to a second embodiment of the present invention. FIG. 8 is a fragmentary enlarged cross-sectional view useful for explaining the relationship between an inlet valve and protuberances of the cylinder block, in which FIG. 8( a ) is a view showing a state before the inlet valve is opened, and FIG. 8( b ) is a view showing a state after the inlet valve is opened. FIG. 9 is a cross-sectional view of the inlet valve after it is opened, as viewed from a different angle. The construction of the wobble plate compressor is identical to that of the wobble plate compressor according to the first embodiment except for the cylinder block, and therefore description thereof is omitted.  
     [0073] This embodiment is distinguished from the first embodiment in that respective bottom surfaces  171   a ,  172   a  of sub-stopper recesses  171 ,  172  are sloped.  
     [0074] The respective bottom surfaces  171   a ,  172   a  of the sub-stopper recesses  171 ,  172  are sloped toward the center of the inlet port  15 .  
     [0075] When the inlet valve  21  is bent into the compression chamber  60 , the two side protuberances  21   e ,  21   f  come into collision with the bottom surfaces  171   a ,  172   a  of the sub-stopper recesses  171 ,  172 . At this time, the side protuberances  21   e ,  21   f  are brought into surface contact with the bottom surfaces  171   a ,  172   a  of the sub-stopper recesses  171 ,  172 , which lessens the impact of the collision.  
     [0076] Further, when the inlet port  21  is bent, the inlet port-blocking portion  21   a  is largely bowed inward at the approximately central portion thereof, which makes it easy to draw in refrigerant gas, thereby further enhancing th suction efficiency.  
     [0077] According to the second embodim nt, it is possible to obtain the same advantageous effects as provided by the first embodiment, as well as lessen the impact of collision of the side protuberances  21   e ,  21   f  of the inlet valve  21  against the bottom surfaces  171   a ,  172   a  of the sub-stopper recesses  171 ,  172 , thereby suppressing noise, and further increasing the suction efficiency by the increase in the bending of the inlet valve  21 .  
     [0078]FIG. 10 is a fragmentary enlarged view of a cylinder block of a wobble plate compressor according to a third embodiment of the present invention. FIG. 11 is a fragmentary enlarged cross-sectional view useful for explaining the relationship between an inlet valve and protuberances of the cylinder block, in which FIG. 11( a ) is a view showing a state before the inlet valve is opened, and FIG. 11( b ) is a view showing a state after the inlet valve is opened. FIG. 12 is a cross-sectional view of the inlet valve after it is opened, as viewed from a different angle. The construction of this wobble plate compressor is identical to that of the wobble plate compressor according to the first embodiment except for the cylinder block, and therefore description thereof is omitted.  
     [0079] This embodiment has features in common with the second embodiment in that bottom surfaces  271   a ,  272   a  of sub-stopper surfaces  271 ,  272  of a cylinder block  201  are sloped toward the center of the inlet port  15 , but is different from the second embodiment in that the sub-stopper recesses  271 ,  272  are located little closer to the central portion of the cylinder block  201  than the sub-stopper recesses  171 ,  172  of the second embodiment are.  
     [0080] According to the third embodim nt, it is possible to obtain the same advantageous effects as provided by the second embodiment.  
     [0081] In the above embodiments, the relationship between the depth of the main stopper recesses  70 ,  170 ,  270  and that of the sub-stopper recesses  71 ,  72 ,  171 ,  172 ,  271 ,  272  is not particularly specified, it is possible to configure, as other embodiments, that the depth of the sub-stopper recesses  71 ,  72 ,  171 ,  172 ,  271 ,  272  is made smaller than that of the main stopper recesses  70 ,  170 ,  270 . This configuration causes, during the suction stroke, first, the two side protuberances  21   e ,  21   f  to collide against the sub-stopper recesses  71 ,  72 ,  171 ,  172 ,  271 ,  272 , and then the central protuberance  21   d  to collide against the main stopper recesses  70 ,  170 ,  270 , which positively suppresses the vibrations of the inlet valve  21 .  
     [0082] Inversely, the depth of the sub-stopper recesses  71 ,  72 ,  171 ,  172 ,  271 ,  272  may be made larger than that of the main stopper recesses  70 ,  170 ,  270 . This configuration causes, during the suction stroke, first, the central protuberance  21   d  to collide against the main stopper recesses  70 ,  170 ,  270 , and then the two side protuberances  21   e ,  21   f  to collide against the sub-stopper recesses  71 ,  72 ,  171 ,  172 ,  271 ,  272 . The timing in which the lift of the side protuberances  21   e ,  21   f  is restricted is delayed relative to the timing in which the lift of the central protuberance  21   d  is restricted, which makes it easy to draw in refrigerant.  
     [0083] In the above embodiments, the two side protuberances  21   e ,  21   f  of the inlet valve  21  are provided at opposite ends of the inlet valve  21  with respect to a direction of the arc thereof, one for each, resp etively, and the two sub-stopper recesses  71  and  72 ,  171  and  172 ,  271  and  272  are formed in the cylinder block  1 ,  101 ,  201 , respectively, in accordance therewith. However, when the side protuberances  21   e ,  21   f  are provided at the opposite ends of the inlet valve  21  with respect to the direction of the arc thereof, two or more for each, respectively, two or more sub-stopper recesses are formed in accordance therewith.  
     [0084] Although in the above embodiments, as an example of the reciprocating refrigerant compressor, the wobble plate compressor is described, the scope of the present invention is not limited to this, but the present invention can be applied to other reciprocating compressors, such as a swash plate compressor.  
     INDUSTRIAL APPLICABILITY  
     [0085] As described heretofore, the reciprocating refrigerant compressor according to the present invention is useful as a refrigerant compressor for an automotive air conditioner, and according to this reciprocating refrigerant compressor, even when the area of inlet ports is increased, large twisting load is not applied to the inlet valves during the suction stroke, and vibrations of the inlet valves are prevented.