KR101676429B1 - Speed reduction device for cold storage warehouse - Google Patents

Abstract

A refrigerating machine according to any one of the preceding claims, wherein the lubricant sealed in the speed reducer (14) is at least 10 占 폚 lower than the target freezing temperature in the freezing warehouse, The viscosity of the base oil at the highest temperature of the lubricant at the time of trial operation prior to the full operation is 15 cSt or more. As a result, the freezing storage gear reducer is obtained which can more effectively prevent the oil leakage and increase the service life of the reducer.

Description

[0001] The present invention relates to a speed reduction device for a cold storage warehouse,

The present invention relates to a speed reducer used in a freezing warehouse.

Since the inside of the freezing warehouse for storing fresh foods and the like is set at a very low temperature, a transporting device such as a storage shelf or transport platform, which is movably installed inside the freezing warehouse, It is necessary to secure a good operation of the decelerator to be used in some form.

Since the speed reducer (or gear motor) is used as a component for driving the conveying device and the like in the freezing warehouse, the speed reducer (or the gear motor) is operated at a room temperature (non-freezing state) It may be operated.

Therefore, in Patent Document 1, there is proposed a structure in which a first oil seal having a temperature characteristic capable of sealing a rotary shaft of a speed reducer within a freezing depot, and a second oil seal mounted on an inner side of a speed reducer of the first oil seal, (Gear motor) having a second oil seal having a high temperature characteristic and devising not to cause oil leakage in both the test operation and the operation in the freezing storage.

Prior art literature

(Patent Literature)

Patent Document 1: Japanese Patent Laid-Open Publication No. 2011-130650

However, even if two kinds of oil seals as described above are provided, damage or abrasion of the tooth surface occurs at the time of the test operation, and the gear reducer (gear motor) is actually mounted on a conveying device or the like in the freezing storage In this case, premature oil leakage may still occur in some cases, and early damage of the speed reducer itself may sometimes occur.

An object of the present invention is to provide a speed reducer for a refrigeration warehouse which can prevent the oil leakage more effectively and increase the service life of the reducer for a longer time.

The present invention relates to a reducer for a refrigeration warehouse used in a refrigeration warehouse, wherein a lubricant sealed in the reducer has a pouring point at least 10 ° C lower than a target refrigeration temperature in the freezing warehouse, The viscosity of the base oil at the maximum temperature of the lubricant at the time of trial operation prior to the start of operation is 15 cSt or more.

The " speed reducer " in the above-described constitution of the present invention includes, in addition to the single speed reducer, a speed reducer which is used in the form of a " gear motor " integrated with the motor and the motor shaft also serves as the input shaft of the speed reducer.

In the present invention, as the lubricant of the speed reducer, a lubricant whose pour point is lower than the target freezing temperature by 10 DEG C or more is used. In addition, the lubricant has a characteristic that the viscosity of the base oil at the highest temperature of the lubricant at the time of the test operation is 15 cSt or more.

As a result, since the oil film can be formed favorably on the tooth surface at the time of the test operation at room temperature, the damage of the tooth surface of the deceleration mechanism during the test operation can be minimized, It is possible to enter a cryogenic operation in an actual refrigeration warehouse in a state in which a clean lubricant (which does not contain abrasive powder) is charged. As a result, it is possible to exert the inherent lubrication performance suitable for cryogenic temperatures over a long period of time.

According to the present invention, it is possible to obtain a reduction gear for a refrigeration warehouse which can prevent leakage of oil more effectively and increase the service life of the reducer for a longer time.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a sectional view of a gear motor provided with a speed reducer for a refrigeration warehouse according to an embodiment of the present invention; FIG.
2 is an enlarged cross-sectional view of a main portion of the gear motor.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a gear motor provided with a reducer for a refrigeration warehouse according to an embodiment of the present invention; FIG. 2 is an enlarged sectional view of a main part of the gear motor; However, the target freezing temperature of the freezing storage (not shown) is -25 ° C in this example.

The freezer storage gear motor 10 is formed by integrating the motor 12 and the speed reducer 14 by fastening the motor casing 12A and the speed reducer casing 14A with bolts 11. The motor (12) has a fan (13) on the side opposite to the load.

The reduction gear 14 includes an input shaft 16 serving as a motor shaft of the motor 12 (supported by a bearing 28), a hypoid pinion 18 formed integrally with the input shaft 16, And a hypoid gear (20) meshing with the gear (18). The hypoid gear 20 is mounted on the intermediate shaft 22 and an intermediate pinion 24 formed integrally with the intermediate shaft 22 meshes with the output gear 26. The rotation of the output gear 26 is output to the outside as the rotation of the output shaft 27.

In the speed reducer 14 according to the present embodiment, depending on the thickness, the size of the reducer casing 14A, or the capacity of the fan 13, even if the lubricant temperature is about 95 Lt; 0 > C or less. However, "room temperature" refers to a range of 20 ° C ± 15 ° C (5-35 ° C) (JIS Z 8703).

In the gear motor 10 according to this embodiment, the input shaft 16 of the speed reducer 14 is composed of a cryogenic temperature oil seal 30 composed of silicone rubber, nitrile rubber or the like and an oil seal 30 made of an acrylic rubber, a nitrile rubber, And is sealed by two kinds of oil seals of the oil seal 32 for room temperature. The output side of the speed reducer 14 is sealed only by the cryogenic oil seal 36 disposed adjacent to the bearing 34 of the output shaft 27 (of the same material as the input side). This is because, on the output side, since the rotation speed is slow and the damage caused by the abrasion powder is not a problem, the cost is reduced. However, an oil seal for room temperature may be provided in parallel with the seal of the output shaft (rotary shaft). In this case, an additional life-enhancing effect of the oil seal is obtained.

Here, the lubricant sealed in the decelerator 14 will be described in detail.

In this speed reducer 14, a lubricant is sealed in the space Sp1 in the speed reducer 14 in Fig. As the lubricant, the " pour point " is at least 10 deg. C or more lower than the target freezing temperature (-25 deg. C in this embodiment) in the freezing storage, and the lubricating agent And the base oil has a viscosity of 15 cSt or more at a temperature (95 DEG C in this embodiment) is used.

Here, the " pour point " is an index showing the fluidity of the lubricant at a low temperature. A pure substance is changed from a liquid to a solid at a constant temperature (melting point), but an indicator which is referred to as a " pour point " is used instead of the melting point because a lubricant which is a mixture of multiple components does not show a definite melting point. According to JIS K2269, the pour point of the lubricant is " a sample taken in a test tube is preheated to 46 deg. C, then cooled by the specified method, and the measurement is started at a temperature 10 deg. C higher than the expected pour point. Is taken out from the cooling bath to observe the temperature at which the test tube does not move at all for 5 seconds even when the test tube is laid down, and a temperature higher by 2.5 [deg.] C than the temperature is defined as the pour point. In the present embodiment, this " pour point " is set to -40 DEG C (the target freezing temperature is -25 DEG C, but is 10 DEG C or more and sufficiently low).

The reason why the pour point of the lubricant is set to -40 DEG C in spite of the target freezing temperature of the refrigeration warehouse according to the present embodiment is -25 DEG C is that the lubricant used in the speed reducer 14 operating in this freezing warehouse is The formation of a good oil film due to subtle shaking or vibration of the shaft or the tooth surface and the affinity with the oil seals 30, 32 and 36 are smoothly performed at the start of operation This may cause durability of the tooth surface or oil leakage.

As described above, in this embodiment, even when the reducer 14 is operated at room temperature for at least one hour, the maximum temperature of the lubricant during the test operation before the full operation of the freezing warehouse is maintained at 95 deg. Therefore, the temperature of 95 DEG C is regarded as " the highest temperature of the test operation before the full operation. &Quot; That is, in this embodiment, the viscosity of the lubricant base oil is set to be 15 cSt or more at a maximum temperature at the time of operating at room temperature for at least one hour, that is, at 95 캜. The numerical value of " 15 cSt or more " is based on the fact that the inventor has confirmed that a problem may actually occur at, for example, about 5 to 10 cSt.

However, " viscosity " is an index indicating ease of flow of the lubricant (thick and thin). Specifically, when the viscosity of a fluid having a resistance of 1 dyne is 0.1 (dyne) when a plate having an area of 1 cm ² is moved at a velocity (V) = 1 cm / s at a film thickness h It is defined as the viscosity of Pascal-second. This is referred to as " absolute viscosity ". Normally, a value obtained by dividing the absolute viscosity by the density of the lubricant is used as " kinematic viscosity ". The numerical value in the present embodiment means a numerical value at "dynamic viscosity". The unit of kinetic viscosity is cSt (mm ² / s).

In the lubricant, by mixing the high viscosity oil and the low viscosity lubricant, a lubricant of essentially any viscosity can be blended. Since the viscosity becomes larger as the temperature becomes lower and becomes lower as the temperature becomes higher depending on the temperature, the viscosity of the lubricant, which normally has good characteristics at a very low temperature, becomes very small under an environment of 95 캜. However, in the present embodiment, the viscosity is intentionally made to be 15 cSt under the environment of 95 캜.

Specifically, in this embodiment, poly alpha-olefin (synthetic oil) is employed as the base oil. By including, for example, lithium or the like in the thickening agent, the viscosity at 15O < 0 > C (15 cSt) can be realized. This lubricant has such characteristics that the viscosity-temperature characteristics are good (high fluidity at low temperature and viscosity is not significantly deteriorated even at high temperature), oxidation stability, lubricity and high temperature resistance are comparatively good. It is a lubricant having characteristics conforming to the purpose.

The seal lubricant sealed in the oil seals 30, 32 and 36 of the speed reducer 14 may basically be the same as the lubricant sealed in the speed reducer 14. In this embodiment, as the seal lubricant, But the viscosity is lower than that of the lubricant to be enclosed in the speed reducer 14 and the viscosity of the lubricant used in the speed reducer 14 is lower than that of the lubricant to be enclosed in the speed reducer 14. [ . That is, roughly speaking, it is a lubricant that is more solid but lighter than the lubricant enclosed in the reducer 14. This is because the seal lubricant of the oil seals 30, 32, and 36 of the speed reducer 14 has a property that the illuminance of the lubricant sealed in the speed reducer 14 is smaller This is because it is possible to further improve the efficiency of the speed reducer 14 because leakage is less likely to occur and the viscosity is lowered. Incidentally, the roughness is an index indicating the apparent aggregation of the lubricant and is slightly different from "viscosity". There are a plurality of kinds of measurement methods of the roughness, but in any case, by using a specified illuminometer, the cone of constant weight touching the surface of the lubricant is introduced into the lubricant for 5 seconds, . In JIS K2220, the concrete measurement method is specified, and the results are classified into nine levels.

Next, the operation of the speed reducer 14 for this refrigeration warehouse will be described.

Since the reducer 14 (or the gear motor 10) is used as a component for driving the conveying device in the freezing storage, etc., the corresponding time is started for the test operation of the conveying device or the like. This test operation is usually performed at room temperature (non-freezing state). In addition, the temperature may be gradually lowered from room temperature to the target freezing temperature during the test operation. Since the temperature of the freezing depot is lowered at a very low speed to prevent dew condensation (when the temperature falls below 0 ° C, it is said to be a reduction rate of 1 ° C per day). As a result, The lubricant is likely to be subjected to a long test operation at a temperature much higher than the target freezing temperature.

However, the lubricant having the optimum characteristics at the cryogenic temperature in the freezing depot is too low in viscosity during such a test operation. This causes premature damage due to difficulty in forming an oil film on the tooth surface, or damage to the tooth surface It is thought that the oil seal is damaged due to the increase of the accompanying abrasion powder. This means that, in other words, at the stage of entering the operation under the original freezing environment, the tooth surface and the oil seal have already undergone considerable damage. Particularly when the decelerating mechanism of the speed reducer 14 is constituted by the orthogonal decelerator such as the hypoid pinion 18 and the hypoid gear 20 that transmit the power by the engagement with the slip as in this embodiment (Although it is not shown, it is interpreted that the worm deceleration mechanism and the like which transmit the power by the engagement with the same slip are also in the same situation).

However, according to the present embodiment, the lubricant sealed in the speed reducer 14 is the highest temperature (the temperature reached when continuous operation is performed at room temperature for 1 hour or more) during the test operation before full-speed operation of the speed reducer 14 Even at 95 ° C, the viscosity of 15 cSt is secured. In general, it can be understood that the " temperature at the time of operation at room temperature for at least one hour " is substantially the temperature that does not rise above that even if continuous operation is performed. Therefore, the setting of the present embodiment means that even if the test operation at room temperature is performed almost unlimitedly, a sufficient oil film is always formed on the tooth surface, and damage is prevented. As a result, generation of abrasive powder is minimized, so that further damage is caused by the influence of the abrasive powder, and a vicious circle in which the oil seals (30, 32, 36) are damaged is also suppressed.

As a result, since the operation can be literally started in a state like a new product when the operation is started under the freezing environment in the freezing warehouse, the lubricant inherently has good characteristics (the pour point is -40 DEG C or lower, And the target freezing temperature is significantly lower than 10 deg. C). In addition, the oil leakage can be effectively prevented and the life of the speed reducer 14 can be prolonged even when the apparatus is operated under the freezing environment.

Particularly, in this embodiment, since the oil seals 30 and 32 are provided with the oil seal 32 for room temperature in addition to the oil seal for cryogenic temperature 30, even if some abrasive dust or the like occurs during the test operation It is possible to satisfactorily prevent the leakage of oil during the test operation and to prevent the wear powder from entering the sliding portion of the cryogenic temperature oil seal 30 So that the sealing function can be maintained satisfactorily for a long period even at the time of operation at the freezing temperature.

The seal lubricant sealed in the oil seals 30, 32 and 36 of the reducer 14 has the same pour point as the lubricant sealed in the reducer 14 but the illuminance is smaller than the lubricant sealed in the reducer 14 And the viscosity is lower than that of the lubricant sealed in the speed reducer 14. This makes it easier to mount the oil seal (compared with the case where the same lubricant as the lubricant in the speed reducer 14 is used as it is) The leakage is less likely to occur, and the efficiency can be further improved.

In the above embodiment, the pour point of the lubricant is set to a value (-40 DEG C or lower) which is sufficiently lower than the target freezing temperature. However, in the present invention, the pour point may not necessarily be lowered. However, from the above-described point of view, it is preferable to use at least a lubricant having a pour point of at least 10 DEG C higher than the target freezing temperature.

In the above embodiment, "the temperature (95 ° C) at the time of operation at room temperature for at least one hour" is set as the "maximum temperature of the lubricant during the test operation before the full operation of the freezing warehouse" So that the test operation can be executed. However, when it is known in advance that the time for the test operation is relatively limited (for example, when the general speed reducer is operated normally, the temperature of 95 ° C becomes the maximum lubricant temperature), the " The maximum temperature suitable for actual test operation may be set as " the maximum temperature of the lubricant at the time of trial operation before operation ". For example, when it is considered that the maximum temperature at the time of test operation prior to full-scale operation is sufficient to anticipate "80 ° C", "a viscosity of 15 cSt at 80 ° C" may be ensured. In this case, since the adaptable temperature range of the lubricant can be further narrowed, there is a possibility that a lubricant with improved characteristics during freezing operation or a lubricant with lower cost can be used. Conversely, for example, when the " temperature " of the installation area is very high, or when it is necessary to frequently perform a high-load test operation, the maximum temperature at the time of trial operation before the full- (For example, 100 DEG C) is set so that " viscosity at 15 DEG C at 100 DEG C " must be secured.

In the above embodiment, the effect of the present invention is particularly remarkable because the hypoid deceleration mechanism, which is an orthogonal decelerator (slipping), is employed as the deceleration mechanism of the decelerator. However, The deceleration mechanism is not particularly limited to the orthogonal deceleration mechanism having a slip. For example, it may be a bevel orthogonal deceleration mechanism with little slippage or a parallel axis deceleration mechanism. Further, it may be a planetary gear reduction mechanism. In either case, a corresponding effect is obtained.

In the above embodiment, two types of oil seals are prepared, one for room temperature use and the other for cryogenic temperature. In addition, as the seal lubricant, the pour point is the same as that of the lubricant sealed in the speed reducer. (Coalesced), and the viscosity is lower than that of the grease lubricant which is enclosed in the speed reducer. However, in the present invention, the oil seal and the seal lubricant are not particularly required to adopt the above-described configuration. Rather, since the burden on the oil seal is alleviated by the present invention, there is a possibility that the structure of the oil seal can be further simplified.

In the present invention, the concrete composition (composition) of the lubricant is also qualitatively expressed as " the pour point is at least 10 deg. C or more lower than the target freezing temperature in the freezing storage, The viscosity of the base oil at the maximum temperature of the lubricant at the time of operation is not less than 15 cSt "is obtained.

Industrial availability

INDUSTRIAL APPLICABILITY The present invention is applicable to a speed reducer used in a freezing warehouse.

The disclosure of Japanese Patent Application No. 2012-082350, filed on March 30, 2012, which is incorporated herein by reference in its entirety, is incorporated herein by reference in its entirety.

10: Gear motor for freezing warehouse
12: Motor
14: Reducer

Claims (7)

1. A speed reducer for a refrigeration warehouse used in a refrigeration warehouse,
The viscosity of the base oil at the maximum temperature of the lubricant at the time of the test operation before the full operation of the freezing depot is lower than the target freezing temperature of the freezing depot, 15 cSt (mm ² / s) or more,
Wherein the seal lubricant of the oil seal of the speed reducer has a pour point that is the same as that of the lubricant sealed in the speed reducer but is smaller than the lubricant sealed in the speed reducer. 1. A speed reducer for a refrigeration warehouse used in a refrigeration warehouse,
The viscosity of the base oil at the maximum temperature of the lubricant at the time of the test operation before the full operation of the freezing depot is lower than the target freezing temperature of the freezing depot, 15 cSt (mm ² / s) or more,
Wherein the seal lubricant of the oil seal of the speed reducer has the same pour point as that of the lubricant sealed in the speed reducer but is lower in viscosity than the lubricant sealed in the speed reducer. 3. The method according to claim 1 or 2,
And the pour point is set to -40 DEG C or less. 3. The method according to claim 1 or 2,
Wherein a maximum temperature of the lubricant at the time of the test operation is set to a temperature when the lubricant is operated at room temperature for at least one hour. 5. The method of claim 4,
Wherein a maximum temperature of the lubricant at the time of the test operation is set at 95 占 폚. 3. The method according to claim 1 or 2,
Wherein the speed reduction mechanism of the speed reducer is constituted by an orthogonal reduction gear mechanism that transmits power by engaging with slippage. delete

Images