JPS601397A - Compressor of variable compression capacity type - Google Patents

Abstract

PURPOSE:To improve the operating property of a control valve at starting and at sharp acceleration, by providing a side plate with plural by-pass holes in different opening positions and using a spool to selectively connect the by-pass holes to a suction side. CONSTITUTION:Two by-pass holes 11b, 11b' are provided in the suction chamber side of a front side plate 3A in such a manner that the by-pass holes are located side by side in the direction of sliding of a spool 19 and are in parallel relation to each other with a wall portion 11d interposed between the holes. At stoppage and at starting, the by-pass hole 11b opened near a high pressure chamber 20 is connected to a suction chamber through the sliding of a slide valve. In operation, a by-pass communication hole 11c is closed by the wall portion 11d located between the by-pass holes 11b, 11b'. At sharp acceleration, the by- pass hole 11b' opened near a low pressure chamber 21 is connected to the suction chamber.

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a variable compression capacity compressor that can automatically control the compression capacity in accordance with changes in the cooling load in a vehicle interior, and more specifically to a compressor that can be used in a suction compartment or a compression compartment. The control valve is provided so that it can be automatically opened and closed by utilizing the change in the differential pressure that occurs between the pressure in the suction stroke (suction stroke pressure PL) and the pressure in the compression stroke in the compression chamber (compression stroke pressure PII). The system is designed so that the compression capacity in the compression chamber can be automatically adjusted by automatically opening and closing the valve to release a portion of the refrigerant gas that is in the middle of compression in the compression chamber to the suction chamber during low cooling loads. This invention relates to an improvement of the control valve mechanism of a variable capacity compressor.

Prior art A variable capacity compressor that automatically controls the compression capacity in response to changes in the cooling load in the vehicle interior utilizes the change in differential pressure that occurs between the pressure in the suction chamber and the pressure in the compression chamber. In other words, when comparing the change in the differential pressure that occurs between the suction stroke pressure Pt and the compression stroke pressure P11, it is found that the change in the differential pressure increases in proportion to the height of the pressure in the suction stroke. In view of this, the present applicant has previously proposed a method of adjusting the compression capacity by automatically opening and closing a control valve mechanism using changes in the differential pressure.

The above proposal consists of a suction chamber (9) as shown in Figures 7 and 8.
A bypass passage (11) is inserted through the front side plate (3A) interposed between the suction chamber (9) and the compression chamber (6) (see Figs. 1 and 2) so as to communicate the suction chamber (9) and the compression chamber (6). In order to control the opening and closing of the bypass path (11), a spool (19) is provided to be slidable in a direction perpendicular to the bypass path (01). ) is provided with a bypass passage (11) so as to be biased in the direction of opening by a spring (221), and a high pressure chamber (20) and a low pressure chamber (21) are arranged on both sides of the spool Q91. The hyperbaric chamber (20) is located in the first
The low pressure chamber (21) is provided so as to communicate with the compression stroke (compression stroke pressure PR) of the compression chamber (6) through the pressure guiding hole (c), and the low pressure chamber (21) is connected to the suction chamber (c) through the second pressure guiding hole (c). 9) Or, the compression chamber (6) is provided so as to communicate with the suction stroke (suction stroke pressure PL), and the differential pressure generated between the compression stroke pressure pn and the suction stroke pressure PL as the pressure increases in the suction stroke (
In the pressure state exceeding the set pressure of 21, the bypass passage 01) is blocked, and the differential pressure generated between the compression stroke pressure PIl and the suction stroke pressure PL as the pressure decreases in the suction stroke By opening the bypass passage (11) and providing a part of the refrigerant gas in the middle of compression to escape to the suction chamber (9), the compressor can be turned off when the cooling load inside the vehicle is large. The compression capacity can be automatically adjusted in response to changes in the cooling load inside the vehicle, so that the compressor can be operated at full capacity, and the operating rate of the compressor can be lowered when the cooling load inside the vehicle is reduced. According to the proposal, a large pressure difference is generated between the compression stroke pressure PII and the suction stroke pressure Pt at the same time as the electromagnetic clutch is connected at the time of startup. Bypass in open state.

Since the path (11) is momentarily closed, it is not possible to sufficiently alleviate the start-up pressure at the time of startup.

■ When the engine is suddenly accelerated during operation, the differential pressure generated between the compression stroke pressure pH and the suction stroke pressure PL becomes even larger, causing the spool noise to move in the direction of blocking the low pressure chamber (2Ij side (old Nokui Pass path)). To do it, 1
The engine rotates at high speed with a cooling load applied, that is, a full-load operating state, and the interior of the vehicle becomes supercooled.

This may cause problems such as:

Purpose of the Invention The present invention is an attempt to improve the conventional situation as described above, and the purpose of the present invention is to improve the operating characteristics of the control valve mechanism during startup and sudden acceleration. .

The structure of the invention, that is, the present invention is characterized in that the torque is reduced at the time of start-up, the start-up shock is alleviated, and full-load operation is prevented during sudden acceleration.
The gist of the present invention is that a high pressure chamber and a low pressure chamber are provided facing each other at both ends of a spool that is provided in a side plate that separates a compression chamber and a suction chamber so as to be able to move forward and backward. A spring is interposed in the low pressure chamber to bias the spool toward the high pressure chamber, and a bypass hole in the side plate that communicates with the high pressure chamber is connected to the compression stroke of the compression chamber. and a plurality of bypass holes communicating with the suction chamber are provided on the suction chamber side with opening positions displaced relative to the bypass holes on the compression chamber side, and the spool is provided with bypass communication holes. one end of the communication hole communicates with the high pressure chamber, and the other end can communicate selectively with the plurality of bypass holes through sliding of the spool, and a wall portion formed between the bypass holes. The main reason is that it is constructed so that it can be closed by.

EXAMPLES Specific examples of the present invention will be described below with reference to illustrative drawings. In each drawing shown in Figures 1 to 6 (1)
indicates the housing that constitutes the outer shell of the compressor. The housing (1) is formed by a front housing (IN) and a rear housing (IB).
In A), a cylinder block (2) is fitted, and a front side plate (3A) and a rear side plate (3B) are fitted on both sides of the cylinder block (2) with the cylinder block (2) in between. The cylinder block (2) is formed into a hollow cylindrical shape with openings at both front and rear ends, and the inner wall surface of the hollow part is formed into a cylindrical shape concentric with the outer peripheral surface of the cylinder block (2). The front and rear openings of the cylinder block (2) are the same as the above-mentioned side doors.

The drive shaft (4) is horizontally suspended between the two side rails (3A) (3B) and is shielded by the cylinder block (2). )
The drive shaft (
A rotor (5) is integrally fixed to the cylinder block (2). A compression chamber (6) is formed between the outer peripheral wall of (5) and the inner wall surface of the cylinder block (2). Also rotor (5)
A vane groove (7) is formed in each vane groove (force), and a vane (8) is inserted into each vane groove so as to be retractable into the compression chamber (6).

front housing (IA) and front side play)
(3A) A suction chamber (9) is provided between the suction chambers (9) and
) is provided with a suction port (9)' connected to a suction pipe (not shown) on the front housing (IA) side. Further, a suction hole (10) is opened in the front side plate (3A) in correspondence with one end of the compression chamber (6), that is, the starting end along the rotational direction of the rotor (5).

On the other hand, at the other end of the compression chamber (6), that is, at a position corresponding to the terminal end along the rotational direction of the rotor (5), a part of the cylinder block (2) is cut out to form a front housing (LA).
A discharge chamber (13) is formed between the discharge chamber (13) and the inner wall surface of the compression chamber (6), and a discharge hole (14) is provided so as to communicate between the discharge chamber (13) and the terminal end of the compression chamber (6). (15) is the same discharge hole (
14) is a discharge valve that controls the discharge valve a9, and (■6) is a zero or rear nose housing (6) that regulates the opening angle of the discharge valve a9.
A lubricating oil separation chamber (17) is formed between the barrier side plate (3B) and the barrier side plate (3B). It is provided so as to communicate with the discharge chamber Q3). A filter (not shown) is provided at the opening of the opening hole (18), and a lubricating oil reservoir separated by the filter is provided in the separation chamber aD. A discharge port connected to a discharge pipe (not shown) is provided on the housing (IB) side.

The front side play) (3A) has a compression chamber (6).
The bypass passage (Il+ (old bypass passage) is located approximately midway between the suction stroke and the compression stroke (at the beginning of the compression stroke) and communicates between the compression chamber (6) and the suction chamber (9). The valve mechanism (formed by the nokuinosis hole (lla), (11bN11b)') and the nokui bus communication hole (llc) drilled in the spool (19) and the opening/closing of the bypass passage (formerly) A control valve mechanism (12) J is provided hereinafter. The control valve mechanism (12) has a spool (Hl
) is slidably provided, and a pair of pressure chambers consisting of a high pressure chamber (20) and a low pressure chamber CD are provided facing each other at both ends of the spool cod. And the low pressure chamber (2I) has a pressure conduction hole (2I).
3) is provided so as to communicate with the suction stroke of the compression chamber (6) through the pressure guiding hole' (231, the tip of which opens at a position that is relatively round to the suction hole 00). In addition, a spring (22) is installed in the low pressure chamber 0υ, and the spool (19
) in the direction of the high pressure chamber (20). At this time, a locking piece 31) is provided on the inner end surface of the plug member (30) that seals the high pressure chamber (20) so as to protrude toward the inside of the high pressure chamber (20), and the end of the spool α9) Even when in contact with the locking piece (31), the bi-
It is configured to ensure communication between the pass communication hole (lie) and the high pressure chamber (20), and by extension the bypass hole (lla). However, the locking piece (31) is attached to the plug member (30).
), instead of protruding from the plug member 00), a groove is formed on the inner end surface of the plug member 00), and the line groove connects the bypass communication hole (lie) and the high pressure chamber (
20) may be configured to communicate with each other. Hyperbaric chamber (2
(1) is the front side play) (3A) compression chamber (6
) through the bypass hole (lla) that opens to the compression chamber (
6), more specifically, a bypass communication hole (ll
c) and a bypass hole (11b) that opens on the suction chamber (9) side of the front side play (3A) in correspondence with the communication groove (lie) on the circumferential surface of the spool outlet that is continuous with the bypass communication hole (llc). )(llb)' through suction chamber (9)
It is set up so that it communicates with the That is, on the suction chamber (9) side of the front side play (3A), there are a plurality of bypass holes (llb) (llb)' between them along the sliding direction of the spool α9). Wall section (lid)
are arranged in parallel.

A bypass communication hole (l) is drilled in the spool (19).
lc) is provided so as to be able to selectively communicate with the bypass holes (llb) and (llb)' through sliding movement of the spool Q9). More specifically, it communicates with the bypass hole (llb) opening to the high-pressure chamber (20) at the time of stopping and starting, and the wall surface formed between the two bypass holes (llb) (llb)' during operation. (l
id) to close the bypass communication hole (llc) and communicate with the low pressure chamber (bypass hole (llb)' which opens toward 2υ) during rapid acceleration.

Next, its effect will be explained.

When the compressor is stopped, each part in the compressor, that is, the suction chamber (9), the compression chamber (6), the discharge chamber a3), and the separation chamber α, are at approximately the same pressure. Also, to the control valve mechanism 02.

Since the high pressure chamber (20) and the low pressure chamber (2I) are in the same pressure state, the spool α9) is spring-loaded as shown in FIG.
The compression chamber (6) and the suction chamber (9) are biased toward the high pressure chamber (20) through the bypass hole (ll).
a), the high pressure chamber (20), the bypass communication hole (lie), and the bypass hole (llb) communicate with each other.

Therefore, when each part is in the above state, the rotor (5) and each vane (8) are connected by transmitting the driving force of the engine to the drive shaft (4) through the connection operation of the electromagnetic clutch (not shown). ... rotational action can be obtained. Through the rotation of each vane (8)..., the refrigerant gas is sent from the evaporator (not shown) into the suction chamber (9) through the suction pipe line and into the compression chamber (6) through the suction hole (10). sucked inside. The refrigerant gas sucked into the compression chamber (6) is gradually compressed while being sent through the compression chamber (6) from its starting end toward its terminal end through the rotational action of the vanes (8). Ru. The refrigerant gas thus sent inside the compression chamber (6) to its terminal position is discharged through the discharge hole 04) and the discharge chamber 03).
, through hole 08), and separation chamber 07), and is sent out from the discharge port (17)' in the discharge pipe toward the condenser (not shown), but as mentioned above, the bypass passage (old) is opened. In other words, the compression chamber (6) and the suction chamber (9) are in a state of
Bypass communication hole (11G) 1. <Inokusu Hole (llb
), a part of the refrigerant gas sent in the compression chamber (6) toward the terminal end along the rotational direction of the rotor (5) as described above is partially compressed during compression. It flows out to the suction chamber (9) side.

In this way, a part of the refrigerant gas in the middle of compression blows through the bypass passage (old) and flows out to the suction chamber (9), thereby making it possible for the refrigerant gas to rise smoothly when starting up the knitting machine. At this time, the pressures (Pn + PL) acting on the high pressure chamber (20) and the low pressure chamber (2I) change as shown in Fig. 9, and the horizontal axis At point (2), the spool reaches the intermediate position described below. (Conventionally, the spool is switched as early as the horizontal axis ■ as shown in Figure 10.) This is because the no-pass gas pressure directly acts on the high pressure chamber (20), which increases the wave-like change in pH. , pressure as a bypass.

This is thought to be because it takes extra time to reach a certain value at 1 because the force is about to be released, but this greatly contributes to reducing the starting torque, which is better than before.

By repeating the rotation of the rotor (5) as described above, the compression pressure in the compression chamber (6) is gradually increased. By sending a portion of the gas into the high pressure chamber (20), the pressure (compression stroke pressure PII) within the high pressure chamber (20) is gradually increased. In this way, the compression stroke pressure pH is increased, and the differential pressure generated between the compression stroke pressure P and the suction stroke pressure PL obtained in the low pressure chamber CD is At this time, the spool α9) overcomes the biasing pressure of the two springs and is pressed toward the low pressure chamber (21).

That is, the high pressure chamber (20) and the low pressure chamber (21) are balanced in the state shown in Fig. 5 (intermediate position), and the spool (bypass communication hole (llc) drilled in the field is ascended to the wall surface (ild)). By blocking the bypass passage aυ in this way, a part of the refrigerant gas in the compression chamber (6) is sucked through the bypass passage (lυ). Room (9
) All of it is compressed and sent through the discharge hole (14), the discharge chamber (13), the through hole T18), and the separation chamber surface to the condenser in one direction through the discharge pipe without flowing out to the Itl. .

In other words, the 100-level operating state is obtained.0 Also, as the cooling load in the single chamber decreases and the pressure in the suction chamber (9) decreases, the differential pressure between the suction stroke pressure Pt and the compression stroke pressure 211 also decreases. 0 and the differential pressure is lower than the set pressure of the spring (22) interposed in the low pressure chamber (21).
The spool α9 was pressed toward the I) side and the wall portion (lid) was blocking the communication hole (lie).
) slides toward the high pressure chamber (20) through the biasing pressure of the spring (22), and a part of the bypass communication hole (llc) communicates with the bypass hole (llb) again, that is, the compression chamber. A part of the refrigerant gas that is being compressed in (6) is released to the suction chamber (9) side, reducing its compression capacity, that is, a so-called partial cooling load operating state is obtained. By separating, the spool (11) returns to the state shown in FIG. 4, that is, the state where the spool (11) is biased toward the high pressure chamber (20) by the spring (221) and the bypass communication hole (llc) and the bypass hole (llb) are aligned. .

On the other hand, when the compressor is suddenly accelerated during operation, as the engine rotational speed increases, the compressor rotational speed also inevitably increases.

As the rotation speed of the compressor increases, the high pressure chamber (
The differential pressure that occurs between the compression stroke pressure PI (at 20) and the suction stroke force PL in the low pressure chamber (2I) will also increase even more.As the differential pressure between the compartments increases in this way, the spool (19) slides further in the low pressure chamber 0υ direction than the state shown in FIG. 5, and as shown in FIG.
By connecting the bypass passage (1υ) in this way, a part of the refrigerant gas that is being compressed in the compression chamber (6) is transferred to the bypass hole (1υ).
11a), high pressure chamber (20), bypass communication hole (lie
), the effect of releasing air to the suction chamber (9) side through the bypass hole (1lb)' is obtained. In addition, as the refrigerant gas in the compression chamber (6) is released to the suction chamber (9) side in this way, the differential pressure that occurs between the compression stroke pressure pn and the suction stroke pressure PL will rapidly decrease. However, as the differential pressure generated between the compression stroke pressure Pa and the suction stroke pressure PL suddenly decreases, the spool (191 spring (221) biases the high pressure chamber toward the high pressure chamber (see Fig. 4). As shown in the figure, the bypass communication hole (llc) and the inlet hole (llb) are in communication, and a part of the refrigerant gas that is being compressed in the compression chamber (6) is transferred to the bypass hole ( 11a), high pressure chamber (20), bypass communication hole (11c), bypass hole (l
The effect of releasing the air to the suction chamber (9) through lb> is obtained. While this relief effect is obtained, the high pressure chamber (20)
The internal pressure will gradually increase, but the compression stroke pressure pH in the high pressure chamber (20) and the low pressure chamber (21
) and the differential pressure generated between the suction stroke pressure PL at
2) In the state where the biasing pressure is exceeded, the spool slide slides toward the low pressure chamber (21), and the bypass communication hole (lie) is closed by the wall portion (lid) again as shown in Fig. 5. Effect of the Invention The present invention is configured as described above, and by having the configuration as described above, it is possible to reduce the start-up torque at the time of startup. As a result, we were able to obtain a smooth start-up.

In addition, when the compressor is suddenly accelerated during operation, it is possible to alleviate the shock that occurs due to the sudden increase in the rotation speed of the compressor, and it is also possible to appropriately deal with overcooling. I was able to do it.

[Brief explanation of drawings]

FIG. 1 is a side cross-sectional view of the compressor according to the present invention (cross-sectional view taken along line A-B-C in FIG. 2), and FIG.
3 is a sectional view taken along line E-E, FIGS. 4 to 6 are enlarged views showing the operating state of the control valve mechanism, and FIG. 7 is a sectional view taken along line D.
Figure 8 is a cross-sectional view of the conventional structure, Figure 8 is a cross-sectional view of the control valve mechanism, Figures 9 and 10 are graphs showing pressure changes in the high-pressure chamber and the low-pressure chamber, respectively. FIG. 9 is related to the present invention, and FIG. 10 is related to the prior art. (1) Housing, (IA) 70nd housing, (I
B) Rear housing, (2) cylinder block, (3
A) Front side plate, (3B) Rear side plate, (4) Drive shaft, (5) Rotor, (6) Compression chamber,
(Cavein groove, (8) vane, (9) suction chamber, (9γ suction port, QQI suction hole, Qll bypass path, (1'1a)
(llb) + (llb)' bypass hole, (llc) bypass communication hole, (lid) wall section, α control valve mechanism, α
3) Discharge chamber, θ4) Discharge hole, (151 discharge valve, 06) Retainer-1Q7) Separation chamber, Hff outlet, (181 hole, (19) Spool, (20) High pressure chamber, GI) Low pressure chamber, (Plastic Spring, (23) Pressure guiding hole. Patent applicant Toyota Automatic Loom Works Co., Ltd. 2nd Section 8 11D Fig. 8 Fig. 9 Fig. 10

Claims (1)

[Claims] (1) A high-pressure chamber and a low-pressure chamber are provided facing each other at both ends of a spool that is movable in a side plate that separates a compression chamber and a suction chamber, and the low-pressure chamber communicates with the suction chamber or the suction stroke of the compression chamber. A spring is inserted in the low pressure chamber to urge the spool toward the high pressure chamber, and a binoculars hole in the side plate that communicates with the high pressure chamber is connected to the compression stroke of the compression chamber. A plurality of bypass passage holes are provided correspondingly and communicated with the suction chamber on the suction chamber side, the opening positions of which are displaced from the bino (spool) holes on the compression chamber side, and bypass communication holes are provided on the spool. A hole is bored, one end of the communication hole communicates with the high pressure chamber, and the other end communicates selectively with the plurality of bypass holes through sliding of the spool, and between the binocular bypass holes. A variable compression capacity type compressor which is provided so as to be closable by a wall portion formed on the wall.