Patent Description:
As a background art of the present invention, there is <CIT> (Patent Document <NUM>). Patent Document <NUM> discloses "a hermetic type scroll compressor which includes a compression mechanism unit including a fixed scroll and an orbiting scroll in an hermetic case, a motor for applying a rotational driving force to the orbiting scroll via a drive shaft, an upper balancer disposed in a cylindrical orbiting space formed in a frame member on a rear side of the orbiting scroll and attached to the drive shaft, a middle balancer attached to the drive shaft or a rotary element of a rotor on an upper side of the motor, and a lower balancer attached to the drive shaft or the rotary element of the rotor on a lower side of the motor, in which a main bearing for supporting the drive shaft is mounted between the upper balancer and the middle balancer, a bearing fitting hole to which the main bearing is fitted is formed below the orbiting space of the frame member, an inner diameter of the bearing fitting hole is formed to be larger than an inner diameter of the orbiting space to coincide with an axial center of the orbiting space, and the bearing is configured to be attachable to the bearing fitting hole in a state in which the main bearing, the upper, middle and lower balancers, and the rotor of the motor are attached to the drive shaft".

<CIT> discloses a scroll type fluid machine that is provided in a motor casing with: a fastening part bearing surface for fastening a motor stator by a fastening member; and a rib for reinforcing the fastening part bearing surface. As a result, the rigidity of the motor casing can be raised to suppress the change in the positional dimension of a positioning pin hole.

<CIT> discloses a scroll fluid machine configured so that a through-hole is formed in a seating surface of a compressor casing, a storage portion is provided in a driving unit casing, the through-hole of the compressor casing is placed at a position offset from a compressor-casing auxiliary crank bearing, and the compressor casing is fastened to the driving unit casing by a fastening member via the through-hole and the storage portion.

<CIT> discloses a scroll-type compressor, in which a first fitting hole is formed on a mounting portion of a front housing to fit a first location pin press-fitted to one end portion of a rear housing, and a second location pin press-fitted to the other end portion of the rear housing, is fitted to a second fitting hole formed on a fitting/inserting portion of a fixed scroll.

<CIT> discloses a scroll fluid machine that can guide a weight to a connection position when the weight is connected to a rotating shaft. The scroll fluid machine comprises an eccentric bushing that is attached to the front end of the rotating shaft. A centrifugal force reduction weight is attached to the rear surface side of a rotary scroll with a rotary bearing interposed therebetween. The centrifugal force reduction weight is connected to the eccentric bushing when a weight part is suitable for the slit of the eccentric bushing. A guiding mechanism comprising an arcuate projection and an arcuate groove which are engaged with each other is provided between the centrifugal force reduction weight and the eccentric bushing.

The hermetic type scroll compressor <NUM> of Patent Document <NUM> is provided on a frame member <NUM> to which a bearing fitting hole <NUM> with a main bearing <NUM> fitted thereto is bolted to a fixed scroll <NUM>. Axial centers of a compression mechanism unit <NUM> and a motor <NUM> are determined by fitting between the bearing fitting hole <NUM> and the main bearing <NUM>, but since the bearing fitting hole <NUM> is provided in the compression mechanism unit <NUM>, it is not easy to separate and connect the compression mechanism unit <NUM> and the motor <NUM>.

Therefore, if the bearing fitting hole <NUM> is provided in a motor frame <NUM>, the compression mechanism unit <NUM> and the motor <NUM> can be easily separated and connected. In this case, even in the scroll-type compressor <NUM> in which the motor <NUM> is built in, all of the compression mechanism unit <NUM>, the motor <NUM>, and their connections can be performed at different factories and places. Further, if the main bearing is provided in the motor frame <NUM>, regardless of whether the motor <NUM> is a built-in scroll-type compressor <NUM>, the compression mechanism unit <NUM> and the motor <NUM> can be operated as a single unit, and the operation can be checked.

However, if the bearing fitting hole <NUM> is provided in the motor frame <NUM>, while aligning the axial center of the orbiting scroll freely rotatable on a certain orbiting radius with an axial center of a shaft eccentric part similarly freely rotatable on the same radius, apart from orbiting scroll, it is necessary to position the compression mechanism unit <NUM> and the motor <NUM> with uniquely fixed positions, which deteriorates the assembling performance.

In view of the above problem, an object of the present invention is to provide a scroll-type compressor in which the main body unit and the motor unit can be separated and connected without being disassembled, while positioning of the eccentric shaft and the non-eccentric part can be performed easily in the same process and a method for manufacturing the same.

In order to solve the above problem, the present invention provides, for example, a scroll-type fluid machine which includes a main body unit having a main body casing, a fixed scroll, and an orbiting scroll provided to face the fixed scroll to make an orbiting motion; and a motor unit having a drive shaft connected to the main body unit to drive the main body unit and a motor casing. A fastening member is provided that fastens the main body unit and the motor unit. The drive shaft protrudes from the motor casing and is attached to a slewing bearing of the main body unit via an eccentric part provided on the motor unit side. The motor casing and the main body casing have positioning holes into which a positioning member is inserted on respective mating surfaces. The positioning member is a separate body from the fastening member. A dimensional difference in an axial direction between an insertion port of the positioning hole on the main body casing side and an end surface of the slewing bearing on the motor casing side is configured to be smaller than a dimensional difference in the axial direction of a tip end on the main body unit side between the drive shaft and the positioning member.

According to the present invention, it is possible to provide a scroll-type compressor in which the main body unit and the motor unit can be separated and connected without being disassembled, while positioning of the eccentric shaft and the non-eccentric part can be performed easily in the same process and a method for manufacturing the same.

A first example of the present invention will be described below with reference to the drawings.

<FIG> illustrates an overall schematic view of a scroll-type fluid machine in this example, and <FIG> illustrates a constitution diagram in which a main body unit and a motor unit of the scroll-type fluid machine are separated from each other.

The scroll-type fluid machine illustrated in <FIG> may be a scroll-type compressor which compresses specific gas or refrigerant such as air or nitrogen, or may be a scroll-type vacuum pump. The scroll-type fluid machine <NUM> includes a main body unit <NUM> and a motor unit <NUM> for driving the main body unit <NUM>, and both of them are fastened by a fastening member <NUM>.

<FIG> illustrates an example of a cross-sectional view of a scroll-type fluid machine <NUM> in <FIG> as seen from the side. As illustrated in <FIG>, an internal structure of the main body unit <NUM> is constituted by a fixed scroll <NUM>, an orbiting scroll <NUM> disposed to face the fixed scroll <NUM>, and a main body casing <NUM> for covering the orbiting scroll <NUM> from an outer side in a radial direction. In the fixed scroll <NUM> and the orbiting scroll <NUM>, spiral wrap parts 5B and 6B are formed on the surfaces of the end plates 5A and 6A, respectively. A compression chamber <NUM> is formed by overlapping wrap parts 5B and 6B of the fixed scroll <NUM> and the orbiting scroll <NUM>. The main body casing <NUM> has a tubular shape, and both ends thereof are open. The fixed scroll <NUM> is attached to an opening portion on one end side of the main body casing <NUM>, and the motor unit <NUM> is attached to an opening portion 7A on the other end side. The orbiting scroll <NUM> is driven by the motor unit <NUM> and makes an orbiting motion. In the main body unit <NUM>, the compression chamber <NUM> defined between the wrap part 5B of the fixed scroll <NUM> and the wrap part 6B of the orbiting scroll <NUM> by the orbiting motion of the orbiting scroll <NUM> is continuously contracted to compress and discharge the fluid. Incidentally, in the present example, the scroll-type fluid machine <NUM> having only a pair of the fixed scroll <NUM> and the orbiting scroll <NUM> has been described as an example, but a configuration which includes the orbiting scroll <NUM> having the wrap part 6B on both sides of the end plate 6A and has the fixed scroll <NUM> on both sides thereof may be provided. The orbiting scroll <NUM> includes a boss portion 10A that accommodates a shaft <NUM> of the motor unit <NUM> on a rear side (a side opposite to a surface on which the wrap part 6B is formed) of the end plate 6A.

As illustrated in <FIG>, the boss portion 10A may be formed on a back side (a surface opposite to the orbiting scroll <NUM>) of a boss plate <NUM> by providing the boss plate <NUM> at a position separated from the back side of the end plate 6A, and may be directly formed on the back side of the end plate 6A of the orbiting scroll <NUM>.

A orbiting bearing <NUM> (11A, 11B, and 11C) which supports a centrifugal force generated by the orbiting motion of the orbiting scroll <NUM> and a gas load generated by compressing the air is formed in a boss portion 10A provided on the back side of the orbiting scroll <NUM>.

A plurality of rotation preventing mechanisms for preventing rotation motion of the orbiting scroll <NUM> is provided between the main body casing <NUM> and the orbiting scroll <NUM>. The rotation preventing mechanism prevents the rotation motion of the orbiting scroll <NUM>, and supports the gas load in an axial direction from the orbiting scroll <NUM>. The rotation preventing mechanism includes an auxiliary crankshaft <NUM> in which two eccentric shafts are integrally formed in the axial direction, are held in the radial direction by a main casing side auxiliary crank bearing <NUM> and rotate following the orbiting scroll <NUM> to prevent rotation of the orbiting scroll <NUM>, an orbiting scroll side auxiliary crank bearing <NUM> which supports the auxiliary crankshaft <NUM> and is accommodated in the orbiting scroll <NUM>, and a main casing side auxiliary crank bearing <NUM> accommodated in the main body casing <NUM>. Incidentally, as a rotation preventing mechanism, instead of the auxiliary crank mechanism described here, for example, a ball coupling mechanism, an Oldham coupling or the like may be used.

As illustrated in <FIG>, the motor unit <NUM> includes a stator <NUM> and a rotor <NUM> that generate power, and a shaft <NUM> that integrates the rotor <NUM> by press fitting or the like and transmits the power to the outside. As the stator <NUM> applies rotational force to the rotor <NUM>, the shaft <NUM> integrated with the rotor <NUM> rotates. The shaft <NUM> has an eccentric part 9A, the eccentric part 9A is accommodated in a boss portion 10A provided on the back side of the orbiting scroll <NUM> when assembling the main body unit <NUM> and the motor unit <NUM> and is attachably and detachably connected to the main body unit <NUM>. The eccentric part 9A of the shaft <NUM> performs an eccentric motion with turning motion of the shaft <NUM>. Therefore, as the shaft <NUM> turns, the orbiting scroll <NUM> connected to the eccentric part 9A makes an orbiting motion. Further, the motor unit <NUM> has a stator <NUM> and a motor casing <NUM> for accommodating the rotor <NUM>. The motor casing <NUM> may be divided into a plurality of components. The motor casing <NUM> is fixed to the stator <NUM> and accommodates the stator <NUM> and the rotor <NUM>. The shaft <NUM> is supported by an output side bearing <NUM> and a counter output side bearing <NUM>. The output side bearing <NUM> and the counter output side bearing <NUM> are disposed coaxially so that the shaft <NUM> is not inclined with respect to the axis of the output side bearing <NUM> and the counter output side bearing <NUM>. This suppresses vibrations generated by the inclination of the shaft <NUM> at the time of the operation of the scroll-type fluid machine <NUM>, suppresses an unbalanced load on the orbiting bearing <NUM>, and prevents a decrease in the service life of the orbiting bearing <NUM>.

Here, when the eccentric part 9A of the shaft <NUM> is provided in the main body unit <NUM>, it is necessary to fasten the shaft <NUM> and the eccentric part 9A using a shaft fastening member such as a coupling. That is, the misalignment occurring between an orbiting center axis of the orbiting scroll <NUM> and the axial center of the shaft <NUM> can be mitigated and adjusted by the shaft fastening member. However, in that case, there is a problem that the number of components increases, the number of processes increases, and an axial dimension length becomes longer. Therefore, it is conceivable to adopt a configuration in which the eccentric part 9A of the shaft <NUM> is provided in the motor unit <NUM>. However, with this configuration, it is necessary to position the main body unit <NUM> and the motor unit <NUM>, while aligning the axial center between the orbiting bearing <NUM> and the eccentric part 9A of the shaft <NUM>, which causes a problem of deteriorating the assembling performance. It is necessary to solve this problem.

The positioning member <NUM> is a member for accurately positioning the main body unit <NUM> and the motor unit <NUM>, and is made separate from the fastening member <NUM>. By separating the positioning member <NUM> and the fastening member <NUM>, deformation of the positioning part generated by the fastening member <NUM> at the time of fastening the main body unit <NUM> and the motor unit <NUM> and core misalignment caused thereby are prevented. The fastening member <NUM> has screw grooves on its surface, but the positioning member <NUM> does not have screw grooves on its surface.

Next, a positional relation between the positioning member <NUM> and the shaft <NUM> will be described. In the scroll-type fluid machine <NUM> having the eccentric part 9A of the shaft <NUM> provided in the motor unit <NUM>, when connecting the main body unit <NUM> and the motor unit <NUM>, it is necessary to align the positions of the centers of the eccentric part 9A and the orbiting scroll wrap part 6B, and align the positions of the main body unit <NUM> and the motor unit <NUM>.

When positioning of the main body unit <NUM> and the motor unit <NUM> is made loose, a positioning jig is required when assembling and reassembling at the time of maintenance. When positioning of the eccentric part 9A and the center of the orbiting scroll wrap part 6B, and positioning of the main body unit <NUM> and the motor unit <NUM> are performed at the same time, for example, a jig for restricting the turning of the eccentric part 9A and the orbiting scroll <NUM> is required.

When positioning the main body unit <NUM> and the motor unit <NUM> is performed earlier than positioning of the eccentric part 9A and the center of the orbiting scroll wrap part 6B, a dimension of the positioning member <NUM> in the axial direction of the shaft <NUM> direction becomes longer, and it is difficult to visually observe a orbiting bearing outer ring 11C in the orbiting bearing <NUM>. Therefore, there are problems in which it is necessary to position the orbiting bearing outer ring 11C before connecting the positioning member <NUM> and it is difficult to adjust the position of the orbiting bearing outer ring 11C after connecting the positioning member <NUM>. In addition, since a contact area between the positioning member <NUM> and the positioning hole 7B increases, the friction at the positioning part when connecting the main body unit <NUM> and the motor unit <NUM> increases, and the workability is deteriorated.

Therefore, by adopting a positioning structure illustrated in <FIG>, workability can be improved. <FIG> is a cross-sectional side view in a separated state of the main body unit <NUM> and the motor unit <NUM> of the scroll-type fluid machine <NUM> in this example. In <FIG>, a protruding dimension of the shaft <NUM> from an entrance of a positioning hole 17A provided in the motor casing <NUM> is defined as a, a length of the positioning member <NUM> protruding from the entrance of the positioning hole 17A is defined as b, and a distance from an entrance of a positioning hole 7B provided in the main body casing <NUM> to an end surface of the orbiting bearing roller 11B on an insertion side of the shaft <NUM> is defined as c.

When the shaft insertion side end surface of the orbiting bearing roller 11B is closer to the motor side than the entrance of the main body casing positioning hole 7B, a relation of formula (<NUM>) or (<NUM>) is established. Also, when the shaft insertion side end surface of the orbiting bearing roller 11B is on a side opposite to the motor from the entrance of the main body casing positioning hole 7B, a relation of formula (<NUM>) is established. <MAT> <MAT> <MAT>.

When positioning the eccentric part 9A and the center of the orbiting scroll wrap part 6B, as a substantial work, positioning of the orbiting bearing <NUM> and the eccentric part 9A is performed. If it is constituted by the dimensions determined by the formulas (<NUM>), (<NUM>) and (<NUM>), when the main body unit <NUM> and the motor unit <NUM> are connected to each other, a tip end of the eccentric part 9A is first inserted into the orbiting bearing <NUM>, and then positioning member <NUM> is connected to the positioning hole 7B. In a state in which the tip end of the eccentric part 9A is inserted into the orbiting bearing <NUM>, the main body unit <NUM> can perform an orbiting motion about the axial center of the shaft <NUM> of the motor unit <NUM>. Therefore, the positioning member <NUM> and the positioning hole 7B can be positioned in a state in which the relative position between the orbiting scroll <NUM> and the eccentric part 9A is determined, a jig is not necessary, the connection between the main body unit <NUM> and the motor unit <NUM> can be performed in the same process, and the assembling performance is improved.

Incidentally, in the drawing of this example, the orbiting bearing <NUM> is a roller bearing, but it may be a ball bearing or a sliding bearing. In the case of the ball bearing or the sliding bearing, a distance from the entrance of the positioning hole 7B provided in the main body casing <NUM> to the ball bearing inner ring or the end surface of the sliding bearing on the side of the motor unit <NUM> is defined as c.

Further, instead of using the positioning member <NUM>, a protruding part may be provided on the main body casing <NUM> or the motor casing <NUM>. By using a protruding part instead of the positioning member, it is possible to reduce the number of components and to improve workability.

Further, instead of using the positioning member <NUM>, a spigot may be provided in the main body casing <NUM> and the motor casing <NUM>. This makes it possible to prevent deformation of the positioning member <NUM> due to the own weight of the main body unit <NUM> or the motor unit <NUM> being applied to the positioning member <NUM> when separating the main body unit <NUM> and the motor unit <NUM>.

Further, the positioning member <NUM> may be a positioning pin. If it is a positioning pin, it can be exchanged when the surface of the positioning part is worn. Furthermore, workability is improved by making the positioning pin a tapered pin.

The number of the positioning members <NUM> may be two or more, and a length h of the positioning member <NUM> may be different. In that case, a protruding length b of the positioning member <NUM> uses the length of the longest positioning member <NUM> in formulas (<NUM>), (<NUM>) and (<NUM>). If the length of the positioning member <NUM> is different, there is no need to simultaneously connect the plurality of positioning members <NUM>, and workability is improved.

Further, the positioning member <NUM> may be fixed to the positioning hole 7B provided in the main body unit <NUM> or may be fixed to the positioning hole 17A provided in the motor unit <NUM>. In a case where the plurality of positioning members <NUM> is provided, one or more positioning members <NUM> may be provided in the positioning hole 7B provided in the main body unit <NUM>, and one or more positioning members <NUM> may be provided in the positioning hole 17A provided in the motor unit <NUM>.

Further, the positioning member <NUM> may be a stepped pin having a large-diameter part and a small-diameter part shorter in the radial direction than the large-diameter part. Therefore, there is an effect in which it is possible to reduce the space of the positioning hole into which the positioning member <NUM> is inserted, and positioning in the axial direction can also be performed.

Further, the positioning hole 7B of the main body casing <NUM> is disposed on the outer side in the radial direction than the rotation preventing mechanism for preventing rotation of the orbiting scroll. This further improves the assembling performance.

In this way, the present example is a scroll-type fluid machine which includes a main body unit having a main body casing, a fixed scroll and an orbiting scroll provided to face the fixed scroll to make an orbiting motion; and a motor unit having a drive shaft connected to the main body unit to drive the main body unit and a motor casing, wherein the drive shaft protrudes from the motor casing and is attached to a slewing bearing of the main body unit, the motor casing and the main body casing have positioning holes into which each of positioning members are inserted on respective facing mating surfaces, and a dimensional difference in an axial direction between an insertion port of the positioning hole on the main body casing side and an end surface of the slewing bearing on the motor casing side is configured to be smaller than a dimensional difference in the axial direction of a tip end on the main body unit side between the drive shaft and the positioning member.

Moreover, provided is a scroll-type fluid machine which includes a main body unit having a main body casing, a fixed scroll and an orbiting scroll provided to face the fixed scroll to make an orbiting motion; and a motor unit having a drive shaft connected to the main body unit to drive the main body unit and a motor casing, wherein the drive shaft protrudes from the motor casing and is attached to a slewing bearing of the main body unit, the motor casing and the main body casing have positioning holes into which the positioning member is inserted on respective mating surfaces, and a dimensional difference in the axial direction between the end surface of the slewing bearing on the motor casing side and the insertion port of the positioning hole on the main body casing side is configured to be smaller than a difference between a protruding dimension of the drive shaft in the axial direction from an insertion port of the positioning hole on the motor casing side and a protruding dimension of the positioning member from the insertion port of the positioning hole on the motor casing side or on the main body casing side.

Further, a method for assembling a fluid machine having a main body unit which expands or compresses a fluid and a motor unit which drives the main body unit, wherein after inserting the drive shaft of the motor unit into the main body unit, the positioning member is inserted into a positioning hole of the motor unit or the main body unit to perform positioning.

Therefore, it is possible to provide a scroll-type fluid machine and a method for assembling the same capable of performing the positioning of the eccentric shaft and the non-eccentric part easily and in the same process, while being capable of separating and connecting the main body unit and the motor unit in a non-disassembled state.

<FIG> is a cross-sectional side view in a separated state of the main body unit and the motor unit of the scroll-type fluid machine in this example. The same constituent elements as those in <FIG> of the first example are denoted by same reference numerals, and the repeated thereof will not be provided. The orbiting bearing <NUM> (11A, 11B, and 11C) and the eccentric part 9A are attached to the main body unit <NUM> or the motor unit <NUM>, to be movable on the circumference of the radius d around the orbiting center of the orbiting scroll <NUM> or the axial center of the shaft <NUM>. In the first example, it is necessary to first insert the leading end of the eccentric part 9A into the orbiting bearing <NUM>, and it is necessary to align the positions of the orbiting bearing <NUM> and the eccentric part 9A movable on the circumference of the radius d around the avial center of the shaft <NUM>. Therefore, by providing the shaft insertion guide part 10B for guiding the shaft <NUM> to the orbiting bearing <NUM> on the side closer the motor unit <NUM> than the orbiting bearing <NUM> of the boss plate <NUM>, it is possible to further improve the workability. The shaft insertion guide part 10B has an inner diameter equal to or larger than the inner diameter of the orbiting bearing roller 11B, and has a chamfer of a width e. The width e is set to formula (<NUM>) when the eccentricity of the eccentric part 9A is defined as d.

By setting the width of the chamfer of the shaft insertion guide part 10B to the formula (<NUM>), if the axial center of the main body unit <NUM> and the axial center of the motor unit <NUM> are roughly aligned and connected, the positions of the eccentric part 9A and the orbiting bearing <NUM> are aligned with each other.

Incidentally, in <FIG>, the chamfer has the width e, but the surface of the shaft insertion guide part 10B may have a curved surface shape.

Claim 1:
A scroll-type fluid machine comprising:
a main body unit (<NUM>) having a main body casing (<NUM>), a fixed scroll (<NUM>), and an orbiting scroll (<NUM>) provided to face the fixed scroll to make an orbiting motion; and
a motor unit (<NUM>) having a drive shaft connected to the main body unit (<NUM>) to drive the main body unit (<NUM>) and a motor casing (<NUM>),
wherein a fastening member (<NUM>) which fastens the main body unit and the motor unit is provided,
wherein the drive shaft protrudes from the motor casing (<NUM>) and is attached to a slewing bearing of the main body unit (<NUM>) via an eccentric part provided on the motor unit side, the motor casing (<NUM>) and the main body casing (<NUM>) have positioning holes into which a positioning member (<NUM>) is inserted on respective mating surfaces,
characterized in that the positioning member (<NUM>) is a separate body from the fastening member (<NUM>), and
a dimensional difference in an axial direction between an end surface of the slewing bearing on the motor casing side and an insertion port of the positioning hole on the main body casing side is smaller than a difference between a protruding dimension of the drive shaft in the axial direction from the insertion port of the positioning hole on the motor casing side and a protruding dimension of the positioning member (<NUM>) from the insertion port of the positioning hole on the motor casing side or on the main body casing side.