Patent Description:
Conventionally, a bottomed cylindrical DI (Drawing&Ironing) can is known. The DI can is manufactured by subjecting a disc-shaped blank made of alloy such as aluminum and iron to cupping and DI processing. In the cupping, the blank is drawn to form a cup-shaped body. In the DI processing, the cup-shaped body is drawn and ironed between a punch and a die while being pressed by a cup holder.

As a can body maker that performs DI processing on the cup-shaped body, for example, one described in <CIT> is known. This can body maker moves a punch linearly in a reciprocating manner in a predetermined stroke direction through a ram shaft by a reciprocating linear motion mechanism.

Specifically, the reciprocating linear motion mechanism includes a mechanism frame (housing) which includes an internal gear centered on a first center axis; a first rotation body which is supported by the mechanism frame to be rotatable around a first center axis; a second rotation body which is supported by the first rotation body to be rotatable around a second center axis separated from the first center axis in parallel and includes an external gear meshing with the internal gear, and an action portion (ram shaft connection part) which is provided in the second rotation body and moved linearly in a reciprocating manner along a predetermined direction orthogonal to the first center axis.

Another reciprocating linear motion mechanism is disclosed in <CIT> forming the basis for the preamble of claim1. Similar reciprocating linear motion mechanisms may also be found in <CIT> and <CIT>.

In the conventional can body maker, it is required to improve the production efficiency of the can. Further, it is required to extend the life of parts of the bearing connecting the first rotation body and the second rotation body to be relatively rotatable. Further, there is room for suppressing the outer shape of the reciprocating linear motion mechanism to be small.

A first object of the present invention is to provide a reciprocating linear motion mechanism for a can body maker and a can body maker capable of improving production efficiency of a can. A second object of the present invention is to provide a reciprocating linear motion mechanism for a can body maker and a can body maker capable of extending the life of parts of a bearing connecting a first rotation body and a second rotation body.

A third object of the present invention is to provide a reciprocating linear motion mechanism for a can body maker and a can body maker capable of suppressing an outer shape of a reciprocating linear motion mechanism to be small.

In the conventional reciprocating linear motion mechanism for the can body maker, the ram shaft connection part and the external gear of the second rotation body are integrally formed with each other by a single member. Therefore, the equipment for manufacturing this member is limited and a manufacturing cost increases. Further, the member including the external gear and the ram shaft connection part needs to be assembled to or separated from the apparatus together during the assembly of the reciprocating linear motion mechanism or the maintenance and replacement (hereinafter, abbreviated as the maintenance or the like) of the bearing or the like connecting the first rotation body and the second rotation body. For this reason, the work became large-scale and took a lot of time and effort.

A fourth object of the present invention is to provide a reciprocating linear motion mechanism for a can body maker and a can body maker capable of easily manufacturing members, reducing a manufacturing cost, and having good workability such as assembly and maintenance.

In the conventional reciprocating linear motion mechanism for the can body maker, there was room for improvement in that oil was stably supplied to the bearing supporting the second rotation body to be rotatable around the second center axis with respect to the first rotation body.

A fifth object of the present invention is to provide a reciprocating linear motion mechanism for a can body maker and a can body maker capable of stably supplying oil to a bearing connecting a first rotation body and a second rotation body.

An aspect of a reciprocating linear motion mechanism for a can body maker of the present invention includes the features of claim <NUM>, particularly a housing including an internal gear centered on a first center axis (for example, in a first radial direction orthogonal to the first center axis); a first rotation body located inside the housing; a first bearing connecting the housing and the first rotation body to be relatively rotatable (for example, around the first center axis); a convex part protruding toward one side of an axis direction from a surface facing one side of the first rotation body in the axis direction and centered on a second center axis parallel to the first center axis; a second rotation body including an external gear meshing with the internal gear about the second center axis and disposed on one side of the first rotation body in the axis direction; a recess which is recessed toward one side in the axis direction from a surface facing the other side of the second rotation body in the axis direction and into which the convex part is inserted; and a second bearing connecting the convex part and the recess to be relatively rotatable (for example, around the second center axis), wherein the internal gear, the external gear, the recess, the second bearing, and the convex part overlap each other when viewed from a radial direction orthogonal to the second center axis (for example, a second radial direction).

According to the present invention, since the axis positions of the internal gear, the external gear, the recess, the second bearing, and the convex part are the same as each other, it is possible to suppress the bulkiness of the axial dimension of the reciprocating linear motion mechanism. Thus, it is possible to suppress the outer shape of the reciprocating linear motion mechanism in the axis direction to be small and to simplify the structure.

Since the outer shape of the reciprocating linear motion mechanism is suppressed to be small, it is possible to reduce the power consumption of the drive motor or the like that drives the reciprocating linear motion mechanism. Therefore, the production efficiency of the can is increased.

Since the axis position of the second bearing connecting the convex part and the recess, that is, the bearing connecting the first rotation body and the second rotation body is the same as the axis position of the meshing portion between the internal gear and the external gear, it is possible to suppress an unbalanced load from acting on the bearing. Accordingly, the load on the bearing is reduced and the life of parts of the bearing can be extended.

The reciprocating linear motion mechanism for the can body maker may further comprise a ram shaft connection part connected to the second rotation body and moved linearly in a reciprocating manner along a predetermined direction (for example, in a first radial direction).

In the reciprocating linear motion mechanism for the can body maker, the second bearing may overlap the internal gear and the external gear over the entire length of the axis direction when viewed from the radial direction (for example, the second radial direction). In this case, since the internal gear and the external gear mesh with each other, it is possible to suppress a load acting on the second bearing from the radial direction from varying at each position of the second bearing in the axis direction. Since a load on the second bearing is equalized in the axis direction, the function of the second bearing is maintained satisfactorily and the frequency of maintenance or the like can be reduced.

In the reciprocating linear motion mechanism for the can body maker, a part of the second bearing and a part of the first bearing may overlap each other when viewed from the axis direction.

For example, according to the configuration of the present invention, the diameter of the first bearing is suppressed to be small compared to a case in which the first bearing does not overlap the second bearing when viewed from the axis direction and disposed on the outside in relation to the second bearing. Therefore, the outer shape of the reciprocating linear motion mechanism can be suppressed to be small.

The reciprocating linear motion mechanism for the can body maker may include a gear which is provided in the first rotation body and is centered on the first center axis.

In this case, the rotational driving force around the first center axis of the first rotation body can be output to the outside of the reciprocating linear motion mechanism through a gear. For example, a cup holder driving mechanism or the like other than the reciprocating linear motion mechanism provided in the can body maker can be stably operated while being synchronized with the operation of the reciprocating linear motion mechanism.

Further, a can body maker of the present invention includes: the reciprocating linear motion mechanism for the can body maker; a ram shaft extending in the predetermined direction and of which one end portion is connected to the ram shaft connection part; a punch disposed at the other end portion of the ram shaft; a die including a through-hole into which the punch is inserted; and a cup holder pressed against an end surface to which the through-hole of the die opens.

According to the reciprocating linear motion mechanism for the can body maker and the can body maker of an aspect of the present invention, the production efficiency of the can can be improved. Further, the life of parts of the bearing connecting the first rotation body and the second rotation body to be relatively rotatable can be extended.

According to the reciprocating linear motion mechanism for the can body maker and the can body maker of an aspect of the present invention, the outer shape of the reciprocating linear motion mechanism can be suppressed to be small.

According to the reciprocating linear motion mechanism for the can body maker and the can body maker of an aspect of the present invention, members are easily manufactured, a manufacturing cost can be reduced, and workability such as assembly and maintenance is good.

According to the reciprocating linear motion mechanism for the can body maker and the can body maker of an aspect of the present invention, oil can be stably supplied to the bearing connecting the first rotation body and the second rotation body.

<FIG> is a partially cross-sectional view showing a state in which an external gear is disposed at a predetermined position around a first center axis with respect to an internal gear and shows a state in which an internal gear flow path and an external gear flow path of a second oil supply path communicate with each other.

A can body maker <NUM> and a reciprocating linear motion mechanism <NUM> for the can body maker <NUM> (hereinafter, simply referred to as the reciprocating linear motion mechanism <NUM> in some cases) of an embodiment of the present invention will be described with reference to the drawings.

As shown in <FIG>, the can body maker <NUM> of the embodiment is a DI can manufacturing apparatus which manufactures a DI can <NUM> by performing DI processing on a cup-shaped body W which is a workpiece.

First, the DI can <NUM> will be described.

The DI can <NUM> is a bottomed cylinder. The DI can <NUM> is used for a can body such as a two-piece can or a bottle can filled and sealed with the contents of a beverage or the like. In the case of the two-piece can, the can body includes the DI can <NUM> and a disc-shaped can lid wrapped around an opening end of the DI can <NUM>. In the case of the bottle can, the can body includes a bottle can body obtained by performing necking, screwing, and the like on the DI can <NUM> and a cap screwed to an opening end of the bottle can body.

The DI can <NUM> is formed into a bottomed cylindrical shape by subjecting a disk-shaped blank punched from a plate material such as an aluminum alloy to a cupping step (drawing step) and a DI step (drawing and ironing step). Specifically, in the case of the two-piece can, for example, the DI can <NUM> is manufactured through a plate material punching step, a cupping step, a DI step, a trimming step, a printing step, an inner surface coating step, a necking step, and a flanging step in this order.

In the process of manufacturing the DI can <NUM>, the blank is subjected to drawing (cupping) by a cupping press and is formed into the cup-shaped body W. That is, the cup-shaped body W is an intermediate produced in the process of transitioning from the blank to the DI can <NUM> in the cupping step. The cup-shaped body W has a bottomed cylindrical shape having a smaller circumferential wall height (a length in the can axis direction) and a larger diameter than the DI can <NUM>.

Next, the can body maker <NUM> will be described.

The can body maker <NUM> is used for the DI step. The can body maker <NUM> performs DI processing, that is, drawing (redrawing) and ironing on the cup-shaped body W to form the DI can <NUM> having a larger circumferential wall height and a smaller diameter than the cup-shaped body W. Further, the can body maker <NUM> forms the can bottom of the DI can <NUM> into a dome shape in the above DI step. That is, in the embodiment, the can formed by the can body maker <NUM> is the DI can <NUM>.

The can body maker <NUM> includes the reciprocating linear motion mechanism <NUM>, a ram shaft <NUM> which extends in a predetermined direction (hereinafter, referred to as a stroke direction S in some cases) in which a ram shaft connection part <NUM> to be described later of the reciprocating linear motion mechanism <NUM> is moved linearly in a reciprocating manner and of which one end portion is connected to the ram shaft connection part <NUM>, a punch <NUM> which is disposed at the other end portion of the ram shaft <NUM>, a ram bearing <NUM> which supports the ram shaft <NUM> to be movable in a reciprocating manner along the axis direction of the center axis O of the ram shaft <NUM>, a die <NUM> which has a through-hole <NUM> into which the punch <NUM> is inserted, a cup holder <NUM> which is pressed against an end surface <NUM> to which the through-hole <NUM> of the die <NUM> opens, and a dormer <NUM> which sandwiches the can bottom of the DI can <NUM> with the punch <NUM> and is formed in a dome shape.

The center axes O of the ram shaft <NUM>, the punch <NUM>, the ram bearing <NUM>, the through-hole <NUM> of the die <NUM>, the cup holder <NUM>, and the dormer <NUM> are arranged coaxially with each other. In the embodiment, the center axis O which is a common axis of these members extends in the horizontal direction.

Further, the can body maker <NUM> includes a cup feeder (not shown) which supplies the cup-shaped body W onto the end surface <NUM> of the die <NUM>, a receiving seat (not shown) which holds the cup-shaped body W on the end surface <NUM>, a can conveying mechanism (not shown) which conveys the formed DI can <NUM> to the outside of the apparatus, an air discharge mechanism (not shown) which discharges air from an air discharge hole opening to at least any one of the front end surface and the outer circumferential surface of the punch <NUM> and separates the DI can <NUM> from the punch <NUM>, a cup holder driving mechanism (not shown) which is driven in synchronization with the reciprocating linear motion mechanism <NUM> and moves the cup holder <NUM> in a reciprocating manner in the axis direction of the center axis O with a stroke length different from that of the ram shaft connection part <NUM> of the reciprocating linear motion mechanism <NUM>, and a drive source (not shown) such as a drive motor.

The reciprocating linear motion mechanism <NUM> converts the rotational driving force around the first center axis C1 input from the drive source into the reciprocating linear motion in the stroke direction S along the center axis O and outputs the result to the ram shaft connection part <NUM>. A detailed configuration of the reciprocating linear motion mechanism <NUM> will be described separately below.

The ram shaft <NUM> has an axial shape extending along the center axis O. The ram shaft <NUM> is slidably supported by the pair of ram bearings <NUM> disposed to be separated from each other in the axis direction of the center axis O.

The punch <NUM> has a cylindrical shape or a columnar shape extending along the center axis O.

The pair of ram bearings <NUM> is disposed between the reciprocating linear motion mechanism <NUM> and the die <NUM> in the axis direction of the center axis O. Of the pair of ram bearings <NUM>, one ram bearing <NUM> disposed at a position close to the die <NUM> is a front bearing 5F and the other ram bearing <NUM> disposed at a position close to the reciprocating linear motion mechanism <NUM> is a rear bearing 5R. The front bearing 5F and the rear bearing 5R have a fluid bearing structure called, for example, a dynamic bearing or a hydrostatic bearing.

A plurality of the dies <NUM> are provided side by side in the axis direction of the center axis O. Each of the plurality of dies <NUM> includes a through-hole <NUM> which penetrates the die <NUM> in the axis direction of the center axis O and has a circular cross-section. The plurality of dies <NUM> include one redrawing die 8A and a plurality of ironing dies (ironing dies) 8B which are located on the side of the dormer <NUM> in relation to the redrawing die 8A. Although particularly not shown, each pilot ring is disposed on the side of the dormer <NUM> in each ironing die 8B. Since the pilot ring is provided, it is possible to suppress the punch <NUM> from contacting each ironing die 8B due to the impact generated when the DI can <NUM> is separated from (passed through) each ironing die 8B in forming.

Further, a coolant liquid for lubricating and cooling is supplied to the redrawing die 8A and each ironing die 8B in forming.

The cup holder <NUM> includes a cylindrical cup holder sleeve 6a which extends in the axis direction of the center axis O. The cup holder sleeve 6a is concentrically disposed on the outside of the punch <NUM> in the radial direction and is movable with respect to the punch <NUM> in the axis direction of the center axis O. The cup holder sleeve 6a is inserted into the cup-shaped body W disposed on the end surface <NUM> of the redrawing die 8A and holds the bottom wall of the cup-shaped body W to be pressed against the end surface <NUM>. That is, the cup holder <NUM> supports the bottom wall of the cup-shaped body W to be pressed against the end surface <NUM> facing the reciprocating linear motion mechanism <NUM> in the die <NUM>.

Although particularly not shown, the cup holder driving mechanism converts the rotational driving force transmitted from the drive source through the reciprocating linear motion mechanism <NUM> into the reciprocating motion in the axis direction of the center axis O and moves the cup holder <NUM> linearly in a reciprocating manner in the axis direction of the center axis O.

The dormer <NUM> is a mold for molding the can bottom of the DI can <NUM>. The dormer <NUM> has a substantially cylindrical shape extending in the axis direction of the center axis O. When the punch <NUM> is disposed at the forward movement end position in the stroke direction S, the dormer <NUM> faces the punch <NUM> in the axis direction of the center axis O.

The air discharge mechanism includes an air discharge hole (not shown) which opens to the outer surface of the punch <NUM>, an air supply path <NUM> to be described later (see <FIG>) of the reciprocating linear motion mechanism <NUM>, an air communication path (not shown) which allows the air discharge hole and the air supply path <NUM> to communicate with each other, and an air supply source (not shown).

Although particularly not shown, the air communication path includes a ram shaft flow path extending through the ram shaft <NUM> in the axis direction of the center axis O. The air supply source is, for example, an air compressor or the like and supplies air (compressed air) to the air supply path <NUM>.

The can body maker <NUM> performs DI processing on the cup-shaped body W as below.

First, the cup-shaped body W which is a workpiece is disposed between the punch <NUM> and the redrawing die 8A in a posture in which the cup shaft (can shaft) is extended in the horizontal direction and the opening thereof is directed toward the punch <NUM>. The bottom wall of the cup-shaped body W faces the end surface <NUM> of the redrawing die 8A.

The cup holder <NUM> and the punch <NUM> are moved forward in the axis direction of the center axis O with respect to the cup-shaped body W. That is, the cup holder <NUM> and the punch <NUM> are moved from the reciprocating linear motion mechanism <NUM> toward the side of the die <NUM>, that is, the front side in the stroke direction S. Then, the cup-shaped body W is subjected to redrawing in such a manner that the punch <NUM> presses the cup-shaped body W into the through-hole <NUM> of the redrawing die 8A while the cup holder <NUM> performs an operation of cup-pressing the bottom wall of the cup-shaped body W against the end surface <NUM> of the redrawing die 8A.

Due to the redrawing, the cup-shaped body W is formed to have a small diameter and a long length in the cup axis direction. Further, ironing is performed while this cup-shaped body W is pressed by the punch <NUM> to sequentially pass through the through-holes <NUM> of the plurality of ironing dies 8B. That is, the circumferential wall of the cup-shaped body W is squeezed and stretched to increase the height of the circumferential wall and decrease the thickness of the circumferential wall so that the shape of the bottomed cylindrical DI can <NUM> is formed. The strength of the DI can <NUM> is increased in such a manner that cold work hardening is performed by squeezing the circumferential wall.

The ironed DI can <NUM> is pressed out from the through-hole <NUM> of the die <NUM> toward the dormer <NUM> by the punch <NUM>. Then, the bottom portion (a portion corresponding to the can bottom) of the DI can <NUM> is pressed between the punch <NUM> and the dormer <NUM> so that the bottom portion of the DI can <NUM> is formed in a dome shape.

Next, the reciprocating linear motion mechanism <NUM> will be described.

As shown in <FIG>, the reciprocating linear motion mechanism <NUM> includes a housing <NUM> having an internal gear <NUM>, a first rotation body <NUM> having a convex part <NUM>, a first bearing <NUM>, a second rotation body <NUM> having a recess <NUM> and an external gear <NUM> meshing with the internal gear <NUM>, a second bearing (bearing) <NUM>, an air joint member <NUM>, a ram shaft connection part <NUM>, a first weight part <NUM>, a second weight part <NUM>, a shaft body <NUM>, the air supply path <NUM>, a first oil supply path <NUM>, a second oil supply path (oil supply path) <NUM>, and a gear (not shown). That is, the reciprocating linear motion mechanism <NUM> includes the convex part <NUM> and the recess <NUM>.

The housing <NUM>, the internal gear <NUM>, a portion other than the convex part <NUM> of the first rotation body <NUM>, the first bearing <NUM>, the shaft body <NUM>, and the gear are centered on the first center axis C1, that is, these members are coaxially disposed with the first center axis C1 as a common axis. The convex part <NUM>, the second rotation body <NUM>, the external gear <NUM>, the recess <NUM>, the second bearing <NUM>, and the air joint member <NUM> are centered on the second center axis C2, that is, these members are coaxially disposed with the second center axis C2 as a common axis.

The first center axis C1 and the second center axis C2 are disposed to be parallel and away from each other. In the embodiment, the first center axis C1 and the second center axis C2 extend in the horizontal direction.

In the description below, the extension direction of the first center axis C1 and the extension direction of the second center axis C2 are simply referred to as the axis direction. In the axis direction, the first rotation body <NUM> and the ram shaft connection part <NUM> are disposed at different positions. In the axis direction, a direction from the first rotation body <NUM> toward the ram shaft connection part <NUM> is referred to as one side in the axis direction and a direction from the ram shaft connection part <NUM> toward the first rotation body <NUM> is referred to as the other side in the axis direction. Additionally, one side in the axis direction may be referred to as the front side and the other side in the axis direction may be referred to as the rear side.

A direction orthogonal to the first center axis C1 is referred to as a first radial direction (radial direction). In the first radial direction, a direction closer to the first center axis C1 is referred to as the inside of the first radial direction and a direction away from the first center axis C1 is referred to as the outside of the first radial direction.

A direction around the first center axis C1 is referred to as a first circumferential direction. In the first circumferential direction, a direction in which the first rotation body <NUM> is rotated with respect to the housing <NUM> at the time of operating the can body maker <NUM> is referred to as a first rotation direction T1.

A direction orthogonal to the second center axis C2 is referred to as a second radial direction (radial direction). In the second radial direction, a direction closer to the second center axis C2 is referred to the inside of the second radial direction and a direction away from the second center axis C2 is referred to as the outside of the second radial direction.

A direction around the second center axis C2 is referred to as a second circumferential direction. In the second circumferential direction, a direction in which the second rotation body <NUM> is rotated with respect to the first rotation body <NUM> at the time of operating the can body maker <NUM> is referred to as a second rotation direction T2.

As shown in <FIG>, the housing <NUM> has a tubular shape centered on the first center axis C1. The housing <NUM> includes an internal gear <NUM> and a housing body <NUM>.

The internal gear <NUM> has an annular shape centered on the first center axis C1. The internal gear <NUM> has a cylindrical shape and extends in the axis direction. The internal gear <NUM> is disposed at one end portion of the housing <NUM> in the axis direction. The internal gear <NUM> is disposed at one opening of the housing <NUM> in the axis direction.

The internal gear <NUM> includes a plurality of internal teeth 16a which are provided on the inner circumferential portion of the internal gear <NUM> to be arranged in the first circumferential direction. The internal teeth 16a are disposed on the inner circumferential portion of the internal gear <NUM> over the entire length of the axis direction. In the embodiment, the internal teeth 16a are exposed to the outside of the reciprocating linear motion mechanism <NUM> through one opening of the housing <NUM> in the axis direction.

The housing body <NUM> has a cylindrical shape centered on the first center axis C1 and extends in the axis direction. The first rotation body <NUM> and the first bearing <NUM> are disposed on the inside of the housing body <NUM>, that is, the inside of the first radial direction. The internal gear <NUM> is fixed to one end portion of the housing body <NUM> in the axis direction.

The housing body <NUM> includes a first outer race support part <NUM>. The first outer race support part <NUM> protrudes inward in the first radial direction from the inner circumferential surface of the housing body <NUM> and extends in the first circumferential direction. The first outer race support part <NUM> has a disc shape centered on the first center axis C1. A pair of plate surfaces of the first outer race support part <NUM> faces the axis direction.

The first rotation body <NUM> is located inside the housing <NUM> in the first radial direction. The first rotation body <NUM> is connected to the housing <NUM> to be relatively rotatable around the first center axis C1.

As shown in <FIG> and <FIG>, the first rotation body <NUM> has a substantially columnar shape centered on the first center axis C1. The first rotation body <NUM> is disposed inside the housing body <NUM>. That is, the first rotation body <NUM> is accommodated in the housing <NUM>.

The first rotation body <NUM> includes a hole portion 21a, a flange portion 21b, and the convex part <NUM>.

The hole portion 21a is recessed from a surface 21e facing the other side of the first rotation body <NUM> in the axis direction toward one side in the axis direction and extends in the axis direction. The hole portion 21a has a circular hole shape centered on the first center axis C1. Specifically, the hole portion 21a is recessed from a portion other than the outer circumferential portion in a surface 21e facing the other side of the first rotation body <NUM> in the axis direction toward one side in the axis direction. That is, the hole portion 21a opens to the other side in the axis direction.

The flange portion 21b is disposed at one end portion of the outer circumferential portion of the first rotation body <NUM> in the axis direction. The flange portion 21b has a disc shape centered on the first center axis C1. The flange portion 21b protrudes outward in the first radial direction from the outer circumferential surface of the first rotation body <NUM> and extends in the first circumferential direction. The pair of plate surfaces of the flange portion 21b faces the axis direction. Of the pair of plate surfaces of the flange portion 21b, the plate surface facing the other side in the axis direction contacts the inner race 31a of the first bearing <NUM> from one side in the axis direction.

The convex part <NUM> will be described below.

The first bearing <NUM> is, for example, a taper roller bearing or the like. The first bearing <NUM> can support a load (radial load) from the first radial direction and a load (axial load) from the axis direction. The first bearing <NUM> connects the housing <NUM> and the first rotation body <NUM> to be relatively rotatable around the first center axis C1.

The first bearing <NUM> includes an inner race 31a, a spacer 31d, an outer race 31b, and a rolling element 31c.

The inner race 31a has a tubular shape centered on the first center axis C1. The inner race 31a is fitted to the outer circumferential surface of the first rotation body <NUM>. A plurality of the inner races 31a are provided side by side in the axis direction. In the embodiment, the first bearing <NUM> includes a pair of the inner races 31a which are arranged with a gap therebetween in the axis direction. The spacer 31d is disposed between the pair of inner races 31a. The spacer 31d has a tubular shape centered on the first center axis C1. The spacer 31d is fitted to the outer circumferential surface of the first rotation body <NUM>.

Of the pair of inner races 31a, the one inner race 31a located on one side in the axis direction is disposed between the flange portion 21b and the spacer 31d in the axis direction. The flange portion 21b contacts the end surface facing one side in the axis direction of one inner race 31a. The spacer 31d contacts the end surface facing the other side in the axis direction of one inner race 31a.

The spacer 31d contacts the end surface facing one side in the axis direction.

The outer race 31b has a tubular shape centered on the first center axis C1. The outer race 31b is located on the outside of the first radial direction in relation to the inner race 31a. The outer race 31b is fitted to the inner circumferential surface of the housing body <NUM>. A plurality of the outer races 31b are provided side by side in the axis direction. In the embodiment, the first bearing <NUM> includes a pair of the outer races 31b which are arranged with a gap therebetween in the axis direction. The first outer race support part <NUM> is disposed between the pair of outer races 31b.

Of the pair of outer races 31b, the first outer race support part <NUM> contacts the end surface facing the other side in the axis direction of the one outer race 31b located at one side in the axis direction.

The first outer race support part <NUM> contacts the end surface facing one side in the axis direction of the other outer race 31b located on the other side in the axis direction in the pair of outer races 31b.

The rolling element 31c is a columnar roller or the like. The rolling element 31c is disposed between the inner race 31a and the outer race 31b in the first radial direction. A plurality of the rolling elements 31c are provided side by side in the first circumferential direction. A plurality of rows of the rolling elements 31c arranged in the first circumferential direction (hereinafter, simply referred to as the rows of the rolling elements 31c) are provided side by side in the axis direction. In the embodiment, the first bearing <NUM> includes a row of a pair of the rolling elements 31c disposed with a gap therebetween in the axis direction.

Of the rows of the pair of rolling elements 31c, the row of the one rolling elements 31c located on one side in the axis direction is rotatably held between one inner race 31a and one outer race 31b.

Of the rows of the pair of rolling elements 31c, the row of the other rolling elements 31c located on the other side in the axis direction is rotatably held between the other inner race 31a and the other outer race 31b.

The convex part <NUM> protrudes from a surface 21d facing one side of the first rotation body <NUM> in the axis direction toward one side in the axis direction and extends in the axis direction. The convex part <NUM> has a columnar shape centered on the second center axis C2. Specifically, the convex part <NUM> protrudes from the outer portion of the first radial direction in the surface 21d facing one side of the first rotation body <NUM> in the axis direction toward one side in the axis direction.

The convex part <NUM> includes an outer circumferential step portion 25a.

The outer circumferential step portion 25a constitutes a part of the outer circumferential portion of the convex part <NUM>. In the example shown in the drawings, the outer circumferential step portion 25a is disposed at the other end portion of the outer circumferential portion of the convex part <NUM> in the axis direction. The outer circumferential step portion 25a has an annular surface shape centered on the second center axis C2 and faces one side in the axis direction.

The second rotation body <NUM> is disposed on one side of the first rotation body <NUM> in the axis direction. The second rotation body <NUM> is connected to the first rotation body <NUM> to be relatively rotatable around the second center axis C2.

As shown in <FIG>, <FIG>, and <FIG>, the second rotation body <NUM> has a substantially eclipsed cylinder shape centered on the second center axis C2. The second rotation body <NUM> includes an external gear <NUM>, a top wall portion (connection part) 22b, a pin member <NUM>, a bolt member <NUM>, a fitting insertion hole 22c, and a recess <NUM>.

The external gear <NUM> has a tubular shape centered on the second center axis C2 and extends in the axis direction. The external gear <NUM> has a substantially cylindrical shape. As shown in <FIG>, the convex part <NUM> is inserted into the external gear <NUM>. A part of a surface 22e facing the other side of the external gear <NUM> in the axis direction faces a part of the surface 21d facing one side of the first rotation body <NUM> in the axis direction with a gap therebetween in the axis direction. The other part of the surface 22e facing the other side of the external gear <NUM> in the axis direction faces a part of the first bearing <NUM> with a gap therebetween in the axis direction.

The external gear <NUM> includes a plurality of external teeth 23a which are provided on the outer circumferential portion of the external gear <NUM> to be arranged in the second circumferential direction. The external teeth 23a are disposed at a portion other than one end portion of the outer circumferential portion of the external gear <NUM> in the axis direction. In the embodiment, the external teeth 23a pass through one opening of the housing <NUM> in the axis direction and are exposed to the outside of the reciprocating linear motion mechanism <NUM>.

At least one or more of the plurality of external teeth 23a and at least one or more of the plurality of internal teeth 16a mesh with each other. The pitch circle diameter of the external teeth 23a of the external gear <NUM> is a half of the pitch circle diameter of the internal teeth 16a of the internal gear <NUM>.

As shown in <FIG>, the external gear <NUM> includes a second outer race support part 23b, a second fitting hole 23c, and a female screw hole 23d.

The second outer race support part 23b protrudes inward in the second radial direction from the inner circumferential surface of the external gear <NUM> and extends in the second circumferential direction. The second outer race support part 23b has a cylindrical shape centered on the second center axis C2. A pair of end surfaces of the second outer race support part 23b faces the axis direction.

The second fitting hole 23c opens to a surface 23e facing one side of the external gear <NUM> in the axis direction. The second fitting hole 23c has a circular hole shape and extends in the axis direction. In the embodiment, the second fitting hole 23c is a retaining hole of which one end portion in the axis direction opens to the surface 23e and the other end portion in the axis direction is closed. In the embodiment, one second fitting hole 23c is provided.

The female screw hole 23d opens to the surface 23e opening to one side of the external gear <NUM> in the axis direction. The female screw hole 23d has a circular hole shape and extends in the axis direction. The female screw hole 23d includes a female screw portion on the inner circumferential surface. In the embodiment, the female screw hole 23d is a retaining hole of which one end portion in the axis direction opens to the surface 23e and the other end portion in the axis direction is closed. A plurality of the female screw holes 23d are provided at intervals in the second circumferential direction. At least one of the plurality of female screw holes 23d is arranged side by side with the second fitting hole 23c in the second circumferential direction. Specifically, in the embodiment, the plurality of female screw holes 23d and the plurality of second fitting holes 23c are arranged in the second circumferential direction on a virtual circle(not shown) centered on the second center axis C2 when viewed from the axis direction (see <FIG>).

In <FIG>, the external gear <NUM> rotates (turns) in the second rotation direction T2 while rotating (revolving) in the first rotation direction T1 along the inner circumferential portion of the internal gear <NUM> at the time of operating the can body maker <NUM>. In the embodiment, when the reciprocating linear motion mechanism <NUM> is viewed from one side in the axis direction, that is, the reciprocating linear motion mechanism <NUM> is viewed from the front side, the first rotation direction T1 is a counterclockwise direction about the first center axis C1 and the second rotation direction T2 is a clockwise direction about the second center axis C2. However, the present invention is not limited thereto. When the reciprocating linear motion mechanism <NUM> is viewed from one side in the axis direction, the first rotation direction T1 may be a clockwise direction about the first center axis C1 and the second rotation direction T2 may be a counterclockwise direction about the second center axis C2.

As shown in <FIG> and <FIG>, the top wall portion 22b is disposed on one side of the external gear <NUM> in the axis direction. The top wall portion 22b is separated from the external gear <NUM> and is located on one side of the external gear <NUM> in the axis direction. That is, the top wall portion 22b and the external gear <NUM> are manufactured as different members. In the embodiment, the top wall portion 22b has a plate shape that spreads in a direction perpendicular to the second center axis C2. The top wall portion 22b is connected to one end portion of the external gear <NUM> in the axis direction and the other end portion of the ram shaft connection part <NUM> in the axis direction. That is, the top wall portion 22b connects the external gear <NUM> and the ram shaft connection part <NUM>. The top wall portion 22b blocks one opening of the external gear <NUM> in the axis direction. The top wall portion 22b may be paraphrased as a closing wall portion 22b or a front wall portion 22b. A surface facing the other side of the top wall portion 22b in the axis direction contacts the surface 23e facing one side of the external gear <NUM> in the axis direction.

As shown in <FIG>, the top wall portion 22b includes a first fitting hole 22f, a bolt insertion hole <NUM>, and a fitting cylinder part 22d.

The first fitting hole 22f penetrates the top wall portion 22b in the axis direction. The first fitting hole 22f has a circular hole shape and extends in the axis direction. The first fitting hole 22f is a through-hole that opens to a surface facing one side of the top wall portion 22b in the axis direction and a surface facing the other side in the axis direction. In the example shown in the drawings, the inner diameter of the first fitting hole 22f is the same as the inner diameter of the second fitting hole 23c. In the embodiment, one first fitting hole 22f is provided.

The bolt insertion hole <NUM> penetrates the top wall portion 22b in the axis direction. The bolt insertion hole <NUM> has a multi-stage circular hole shape and extends in the axis direction. The bolt insertion hole <NUM> is a through-hole opening to a surface facing one side of the top wall portion 22b in the axis direction and a surface facing the other side in the axis direction. A plurality of the bolt insertion holes <NUM> are provided at intervals in the second circumferential direction. At least one of the plurality of bolt insertion holes <NUM> is provided side by side with the first fitting hole 22f in the second circumferential direction. Specifically, in the embodiment, the plurality of bolt insertion holes <NUM> and the plurality of first fitting holes 22f are arranged in the second circumferential direction on a virtual circle (not shown) centered on the second center axis C2 when viewed from the axis direction (see <FIG>).

As shown in <FIG>, the bolt insertion hole <NUM> includes a head portion arrangement portion <NUM>, a shaft portion arrangement portion 22i, and a step portion 22j.

The head portion arrangement portion <NUM> is located at a portion on one side of the bolt insertion hole <NUM> in the axis direction. The head portion arrangement portion <NUM> opens to one surface of the top wall portion 22b in the axis direction and extends in the axis direction. The head portion arrangement portion <NUM> has a circular hole shape.

The shaft portion arrangement portion 22i is located at a portion on the other side of the bolt insertion hole <NUM> in the axis direction. The shaft portion arrangement portion 22i opens to the other surface of the top wall portion 22b in the axis direction and extends in the axis direction. The shaft portion arrangement portion 22i has a circular hole shape. The inner diameter of the shaft portion arrangement portion 22i is smaller than the inner diameter of the head portion arrangement portion <NUM>. The shaft portion arrangement portion 22i and the head portion arrangement portion <NUM> communicate with each other.

The step portion 22j is disposed between the head portion arrangement portion <NUM> and the shaft portion arrangement portion 22i. The step portion 22j has an annular surface shape spreading in a direction perpendicular to the second center axis C2 and faces one side in the axis direction.

The fitting cylinder part 22d protrudes toward the other side in the axis direction from the surface facing the other side of the top wall portion 22b in the axis direction. The fitting cylinder part 22d has a tubular shape centered on the second center axis C2. The fitting cylinder part 22d is inserted into the external gear <NUM>. The fitting cylinder part 22d is fitted to the inner circumferential surface of the external gear <NUM>. That is, the fitting cylinder part 22d is fitted to the hole portion <NUM>.

The pin member <NUM> has a columnar shape extending in the axis direction. The pin member <NUM> is inserted through the first fitting hole 22f and the second fitting hole 23c. The pin member <NUM> is fitted to the inner circumferential surfaces of the first fitting hole 22f and the second fitting hole 23c. That is, the pin member <NUM> is fitted to the first fitting hole 22f and the second fitting hole 23c. In the embodiment, one pin member <NUM> is provided.

The bolt member <NUM> has a multi-stage columnar shape extending in the axis direction. The bolt member <NUM> is inserted into the bolt insertion hole <NUM> and is screwed into the female screw hole 23d. The top wall portion 22b and the external gear <NUM> are fixed to each other by the bolt member <NUM>.

The bolt member <NUM> includes a shaft portion 24a having a male screw portion formed on the outer circumferential surface and a head portion 24b having an outer diameter larger than that of the shaft portion 24a.

The male screw portion of the shaft portion 24a is screwed to the female screw portion of the female screw hole 23d. One end portion of the shaft portion 24a in the axis direction is disposed inside the shaft portion arrangement portion 22i.

The head portion 24b is disposed inside the head portion arrangement portion <NUM>. An end surface facing the other side of the head portion 24b in the axis direction contacts the step portion 22j.

The outer diameter of one end portion of the shaft portion 24a in the axis direction is smaller than the inner diameter of the shaft portion arrangement portion 22i. The outer diameter of the head portion 24b is smaller than the inner diameter of the head portion arrangement portion <NUM>. Therefore, a gap is provided between the outer circumferential surface of the bolt member <NUM> and the inner circumferential surface of the bolt insertion hole <NUM>.

As shown in <FIG> and <FIG>, a plurality of the bolt members <NUM> are provided. The plurality of bolt members <NUM> are arranged at intervals in the second circumferential direction. At least one of the plurality of bolt members <NUM> is provided side by side with the pin member <NUM> in the second circumferential direction. Specifically, in the embodiment, as shown in <FIG>, the plurality of bolt members <NUM> and the plurality of pin members <NUM> are arranged in the second circumferential direction on a virtual circle (not shown) centered on the second center axis C2 when viewed from the axis direction. In the example shown in the drawings, at least one of the plurality of bolt members <NUM> is disposed inside the tubular ram shaft connection part <NUM> when viewed from the axis direction.

As shown in <FIG>, the fitting insertion hole 22c penetrates the top wall portion 22b in the axis direction. The fitting insertion hole 22c has a circular hole shape centered on the second center axis C2.

The recess <NUM> is recessed from the surface 22e facing the other side of the second rotation body <NUM> in the axis direction toward one side in the axis direction and extends in the axis direction. The recess <NUM> has a circular hole shape centered on the second center axis C2. Specifically, the recess <NUM> is recessed from an inner portion of the second radial direction in the surface 22e facing the other side of the external gear <NUM> in the axis direction toward one side in the axis direction. That is, the recess <NUM> opens to the other side in the axis direction. One end portion of the recess <NUM> in the axis direction is blocked by the top wall portion 22b. The convex part <NUM> is inserted into the recess <NUM>.

The second bearing <NUM> is, for example, a taper roller bearing or the like. The second bearing <NUM> can support a load (radial load) from the second radial direction and a load (axial load) from the axis direction. The second bearing <NUM> is interposed between the inner circumferential surface of the external gear <NUM>, that is, the inner circumferential surface of the recess <NUM> and the outer circumferential surface of the convex part <NUM>. The second bearing <NUM> connects the convex part <NUM> and the recess <NUM> to be relatively rotatable around the second center axis C2. That is, the second bearing <NUM> connects the first rotation body <NUM> and the second rotation body <NUM> to be relatively rotatable around the second center axis C2.

The second bearing <NUM> includes an inner race 32a, a spacer 32d, an outer race 32b, and a rolling element 32c.

The inner race 32a has a tubular shape centered on the second center axis C2. The inner race 32a is fitted to the outer circumferential surface of the convex part <NUM>. A plurality of the inner races 32a are provided side by side in the axis direction. In the embodiment, the second bearing <NUM> includes a pair of the inner races 32a disposed with a gap therebetween in the axis direction. The spacer 32d is disposed between the pair of inner races 32a. The spacer 32d has a tubular shape centered on the second center axis C2. The spacer 32d is fitted to the outer circumferential surface of the convex part <NUM>.

Of the pair of inner races 32a, the one inner race 32a located on one side of the axis direction is disposed between the spacer 32d and an inner ring retainer <NUM> to be described later of the air joint member <NUM> in the axis direction. The inner ring retainer <NUM> contacts the end surface facing one side of one inner race 32a in the axis direction. The spacer 32d contacts the end surface facing the other side of one inner race 32a in the axis direction. That is, one inner race 32a is sandwiched by the inner ring retainer <NUM> and the spacer 32d from both sides in the axis direction.

Of the pair of inner races 32a, the other inner race 32a located on the other side in the axis direction is disposed between the spacer 32d and the outer circumferential step portion 25a in the axis direction. The spacer 32d contacts the end surface facing one side of the other inner race 32a in the axis direction. The outer circumferential step portion 25a contacts the end surface facing the other side of the other inner race 32a in the axis direction. That is, the other inner race 32a is sandwiched by the spacer 32d and the outer circumferential step portion 25a from both sides in the axis direction.

Further, although particularly not shown, the surface 21d facing one side of the first rotation body <NUM> in the axis direction may contact an end surface facing the other side of the other inner race 32a in the axis direction. In this case, the other inner race 32a is sandwiched by the spacer 32d and the surface 21d facing one side of the first rotation body <NUM> in the axis direction from both sides in the axis direction.

The outer race 32b has a tubular shape centered on the second center axis C2. The outer race 32b is located on the outside of the second radial direction in relation to the inner race 32a. The outer race 32b is fitted to the inner circumferential surface of the external gear <NUM>, that is, the inner circumferential surface of the recess <NUM>. A plurality of the outer races 32b are provided side by side in the axis direction. In the embodiment, the second bearing <NUM> includes a pair of the outer races 32b disposed with a gap therebetween in the axis direction. The second outer race support part 23b is disposed between the pair of outer races 32b.

Of the pair of outer races 32b, the second outer race support part 23b contacts the end surface facing the other side in the axis direction of one outer race 32b located on one side in the axis direction.

Of the pair of outer races 32b, the second outer race support part 23b contacts the end surface facing one side in the axis direction of the other outer race 32b located on the other side in the axis direction.

The rolling element 32c is a columnar roller or the like. The rolling element 32c is disposed between the inner race 32a and the outer race 32b in the second radial direction. A plurality of the rolling elements 32c are provided side by side in the second circumferential direction. A plurality of rows of the rolling elements 32c arranged in the second circumferential direction (hereinafter, simply referred to as the rows of the rolling elements 32c) are provided side by side in the axis direction. In the embodiment, the second bearing <NUM> includes a row of a pair of the rolling elements 32c disposed with a gap therebetween in the axis direction.

Of the rows of the pair of rolling elements 32c, the row of one rolling elements 32c located on one side of the axis direction is rotatably held between one inner race 32a and one outer race 32b.

Of the rows of the pair of rolling elements 32c, the row of the other rolling elements 32c located on the other side in the axis direction is rotatably held between the other inner race 32a and the other outer race 32b.

The internal gear <NUM>, the external gear <NUM>, the recess <NUM>, the second bearing <NUM>, and the convex part <NUM> overlap each other when viewed from the second radial direction. That is, the internal gear <NUM>, the external gear <NUM>, the recess <NUM>, the second bearing <NUM>, and the convex part <NUM> respectively include a portion disposed at the same position in the axis direction. The second bearing <NUM> is disposed to overlap the internal gear <NUM> and the external gear <NUM> over the entire length in the axis direction when viewed from the second radial direction.

A part of the second bearing <NUM> in the second circumferential direction and a part of the first bearing <NUM> in the first circumferential direction are disposed to overlap each other when viewed from the axis direction. That is, a part of the second bearing <NUM> overlaps a part of the first bearing <NUM> when viewed from the axis direction.

The air joint member <NUM> is attached to the convex part <NUM> and the top wall portion 22b. The air joint member <NUM> is formed such that air can flow therein and constitutes a part of the flow path of the air supply path <NUM>.

The air joint member <NUM> includes an inner ring retainer <NUM>, an outer cylinder <NUM>, and an inner cylinder <NUM>.

The inner ring retainer <NUM> has a disc shape centered on the second center axis C2 to spread in a direction perpendicular to the second center axis C2. A plate surface facing the other side of the inner ring retainer <NUM> in the axis direction contacts the surface facing one side of the convex part <NUM> in the axis direction. The inner ring retainer <NUM> is fixed to the convex part <NUM> by screwing or the like. The outer circumferential portion of the inner ring retainer <NUM> protrudes outward in the second radial direction in relation to the outer circumferential surface of the convex part <NUM>. The outer circumferential portion of the inner ring retainer <NUM> contacts one inner race 32a of the second bearing <NUM> from one side in the axis direction. That is, the inner ring retainer <NUM> presses the inner race 32a of the second bearing <NUM> from one side in the axis direction.

The inner ring retainer <NUM> includes a retainer air hole 41a.

The retainer air hole 41a penetrates the inner ring retainer <NUM> in the axis direction. The retainer air hole 41a has a circular hole shape centered on the second center axis C2.

The outer cylinder <NUM> has a cylindrical shape centered on the second center axis C2 and extends in the axis direction. The outer cylinder <NUM> is inserted into the fitting insertion hole 22c. The outer cylinder <NUM> is fitted to the inner circumferential surface of the fitting insertion hole 22c. The outer cylinder <NUM> is fixed to the top wall portion 22b by screwing or the like.

The outer cylinder <NUM> includes an outer cylinder air hole 42a.

The outer cylinder air hole 42a penetrates the circumferential wall of the outer cylinder <NUM> in the second radial direction. The outer cylinder air hole 42a is located on a virtual line connecting the second center axis C2 and the center axis A of the ram shaft connection part <NUM> when viewed from the axis direction.

The inner cylinder <NUM> has an eclipsed cylinder shape centered on the second center axis C2 and extends in the axis direction. The other end portion of the inner cylinder <NUM> in the axis direction contacts the plate surface facing one side of the inner ring retainer <NUM> in the axis direction. The inside of the inner cylinder <NUM> communicates with the retainer air hole 41a of the inner ring retainer <NUM>. The inner cylinder <NUM> is fixed to the inner ring retainer <NUM> by screwing or the like. That is, the inner cylinder <NUM> is fixed to the convex part <NUM> through the inner ring retainer <NUM>. The inner cylinder <NUM> and the outer cylinder <NUM> are relatively rotatable around the second center axis C2.

The inner cylinder <NUM> includes an inner cylinder air groove 43a and an inner cylinder air hole 43b.

The inner cylinder air groove 43a is recessed inward in the second radial direction from the outer circumferential surface of the inner cylinder <NUM> and extends in the second circumferential direction. The inner cylinder air groove 43a has an annular shape centered on the second center axis C2. The inner cylinder air groove 43a communicates with the outer cylinder air hole 42a.

The inner cylinder air hole 43b penetrates the circumferential wall of the inner cylinder <NUM> in the second radial direction. The inner cylinder air hole 43b extends in the second radial direction and opens to the inner circumferential surface of the inner cylinder <NUM> and the inner cylinder air groove 43a. The inside of the inner cylinder <NUM> and the inner cylinder air groove 43a communicate with each other through the inner cylinder air hole 43b. A plurality of the inner cylinder air holes 43b are provided side by side in the second circumferential direction. The plurality of inner cylinder air holes 43b are arranged radially around the second center axis C2.

As shown in <FIG>, the ram shaft connection part <NUM> is connected to the second rotation body <NUM> and is moved linearly in a reciprocating manner along a predetermined direction (stroke direction S) in the first radial direction. The ram shaft connection part <NUM> has a bottomed cylindrical shape and extends in the axis direction. The ram shaft connection part <NUM> opens to one side in the axis direction.

The ram shaft connection part <NUM> protrudes from the top wall portion 22b toward one side in the axis direction. The ram shaft connection part <NUM> is located on one side in the axis direction in relation to the housing <NUM>. The ram shaft connection part <NUM> protrudes from the top wall portion 22b toward the outside of the second radial direction. In the embodiment, a part of the ram shaft connection part <NUM> (a part other than an air cylinder 35a to be described later) is integrally formed with the top wall portion 22b.

The center axis A of the ram shaft connection part <NUM> is parallel to the first center axis C1. The center axis A of the ram shaft connection part <NUM> is disposed in parallel to the second center axis C2 to be away therefrom. The distance between the center axis A and the second center axis C2 in the second radial direction is the same as the distance between the first center axis C1 and the second center axis C2 in the second radial direction. When the reciprocating linear motion mechanism <NUM> is viewed from the axis direction, the center axis A of the ram shaft connection part <NUM> is located on the pitch circle diameter of the external teeth 23a of the external gear <NUM>.

The ram shaft connection part <NUM> includes an air cylinder 35a.

The air cylinder 35a is disposed inside the ram shaft connection part <NUM>. The air cylinder 35a has a tubular shape centered on the center axis A and extends in the axis direction. The air cylinder 35a is formed such that air can flow therein and constitutes a part of the flow path of the air supply path <NUM>.

In <FIG>, the ram shaft connection part <NUM> is connected to the ram shaft <NUM> through a connection bearing <NUM> (see <FIG>) provided in the outer circumferential portion of the ram shaft connection part <NUM>. The connection bearing <NUM> connects the ram shaft connection part <NUM> and the ram shaft <NUM> to be relatively rotatable around the center axis A.

As shown in <FIG> and <FIG>, the first weight part <NUM> is connected to the first rotation body <NUM> and is located on the side opposite to the second center axis C2 with the first center axis C1 interposed therebetween in the first radial direction. The first weight part <NUM> functions as a so-called counterweight for maintaining a good rotational balance in the first circumferential direction when the first rotation body <NUM>, the convex part <NUM>, the second bearing <NUM>, the second rotation body <NUM>, the recess <NUM>, the ram shaft connection part <NUM>, and the second weight part <NUM> rotate around the first center axis C1.

The first weight part <NUM> is disposed on one side of the first rotation body <NUM> in the axis direction. The first weight part <NUM> has a semicircular plate shape. A surface facing the other side of the first weight part <NUM> in the axis direction contacts the surface 21d facing one side of the first rotation body <NUM> in the axis direction. An outer end portion, that is, an outer circumferential portion of the first weight part <NUM> in the first radial direction protrudes outward in the first radial direction in relation to the outer circumferential surface of the first rotation body <NUM>. The outer circumferential portion of the first weight part <NUM> overlaps the first bearing <NUM> when viewed from the axis direction.

The first weight part <NUM> is fixed to the first rotation body <NUM> by a plurality of bolt members <NUM> arranged in the first circumferential direction. Each bolt member <NUM> extends in the axis direction. Each bolt member <NUM> is inserted into the bolt insertion hole penetrating the first weight part <NUM> in the axis direction and is screwed into the female screw hole of the first rotation body <NUM>.

As shown in <FIG> and <FIG>, the second weight part <NUM> is connected to the second rotation body <NUM> and is located on the side opposite to the ram shaft connection part <NUM> with the second center axis C2 interposed therebetween in the second radial direction. The second weight part <NUM> functions as a so-called counterweight for maintaining a good rotational balance in the second circumferential direction when the second rotation body <NUM> and the ram shaft connection part <NUM> rotate around the second center axis C2.

The second weight part <NUM> protrudes outward in the second radial direction from the top wall portion 22b. The second weight part <NUM> and the top wall portion 22b have a substantially disc shape as a whole. The second weight part <NUM> is integrally formed with a part of the ram shaft connection part <NUM> and the top wall portion 22b.

As shown in <FIG>, the shaft body <NUM> has a multi-stage columnar shape centered on the first center axis C1 and extends in the axis direction. The shaft body <NUM> is disposed on the other side of the first rotation body <NUM> in the axis direction. The outer diameter of the shaft body <NUM> is smaller than the outer diameter of the first rotation body <NUM>. The outer diameter of one end portion of the shaft body <NUM> in the axis direction is larger than the outer diameter of the portion other than the one end portion of the shaft body <NUM> in the axis direction. One end portion of the shaft body <NUM> in the axis direction is fitted into the opening portion of the hole portion 21a of the first rotation body <NUM>. One end portion of the shaft body <NUM> in the axis direction is fixed to the other end portion of the first rotation body <NUM> in the axis direction by a screw member or the like. That is, the shaft body <NUM> is fixed to the first rotation body <NUM>.

The shaft body <NUM> is supported by a third bearing (not shown) to be rotatable around the first center axis C1. The rotational driving force of the first rotation direction T1 is input from a drive source (not shown) to the shaft body <NUM>. The shaft body <NUM> and the first rotation body <NUM> are rotated in the first rotation direction T1 with respect to the housing <NUM> by the rotational driving force of the drive source.

The air supply path <NUM> is an air flow path which is formed inside the reciprocating linear motion mechanism <NUM>. The air supply path <NUM> extends inside the shaft body <NUM>, inside the first rotation body <NUM>, inside the convex part <NUM>, inside the air joint member <NUM>, inside the top wall portion 22b of the second rotation body <NUM>, and inside the ram shaft connection part <NUM>.

The air supply path <NUM> includes a first air flow path 28a, an air chamber <NUM>, a second air flow path 28b, an air joint flow path 28c, a third air flow path 28d, and a fourth air flow path 28e. The first air flow path 28a, the air chamber <NUM>, the second air flow path 28b, the air joint flow path 28c, the third air flow path 28d, and the fourth air flow path 28e communicate with each other. Air supplied from an air supply source (not shown) to the air supply path <NUM> flows through the air supply path <NUM> from the upstream side to the downstream side in order of the first air flow path 28a, the air chamber <NUM>, the second air flow path 28b, the air joint flow path 28c, the third air flow path 28d, and the fourth air flow path 28e.

The first air flow path 28a is disposed inside the shaft body <NUM>. In the embodiment, the first air flow path 28a is located at the other end portion of the shaft body <NUM> in the axis direction and extends on the first center axis C1 in the axis direction.

The air chamber <NUM> is disposed inside the shaft body <NUM> and the first rotation body <NUM>. The air chamber <NUM> is formed over a portion other than the other end portion of the shaft body <NUM> in the axis direction and the hole portion 21a of the first rotation body <NUM>. The air chamber <NUM> extends on the first center axis C1 in the axis direction. The air chamber <NUM> has the largest flow path cross-sectional area and the largest volume among the flow paths constituting the air supply path <NUM>. The air chamber <NUM> can temporarily store air (compressed air) inside the air chamber <NUM>.

The second air flow path 28b is disposed inside the first rotation body <NUM> and the convex part <NUM>. The second air flow path 28b extends on the second center axis C2 in the axis direction. The other end portion of the second air flow path 28b in the axis direction opens into the hole portion 21a. One end portion of the second air flow path 28b in the axis direction opens to a surface facing one side of the convex part <NUM> in the axis direction.

The air joint flow path 28c includes a retainer air hole 41a, an inside (inner space) of an inner cylinder <NUM>, an inner cylinder air hole 43b, an inner cylinder air groove 43a, and an outer cylinder air hole 42a. Air flowing from the second air flow path 28b into the air joint flow path 28c flows through the retainer air hole 41a, the inner cylinder <NUM>, the inner cylinder air hole 43b, the inner cylinder air groove 43a, and the outer cylinder air hole 42a in this order and flows out to the third air flow path 28d.

The third air flow path 28d is disposed inside the top wall portion 22b and extends in the second radial direction. The third air flow path 28d extends along a virtual line connecting the second center axis C2 and the center axis A of the ram shaft connection part <NUM> when viewed from the axis direction. An inner end portion of the third air flow path 28d in the second radial direction is connected to the outer cylinder air hole 42a. An outer end portion of the third air flow path 28d in the second radial direction is blocked by a plug 28f.

The fourth air flow path 28e is disposed inside the ram shaft connection part <NUM>. The fourth air flow path 28e extends on the center axis A of the ram shaft connection part <NUM> in the axis direction. The other end portion of the fourth air flow path 28e in the axis direction is connected to the third air flow path 28d. One end portion of the fourth air flow path 28e in the axis direction is connected to an air communication path (not shown). A portion other than the other end portion of the fourth air flow path 28e in the axis direction is formed by (the inner space of) the air cylinder 35a.

The first oil supply path <NUM> penetrates the housing <NUM> and supplies oil to the first bearing <NUM>. In the embodiment, the first oil supply path <NUM> penetrates the circumferential wall of the housing body <NUM>. An outer end portion of the first oil supply path <NUM> in the first radial direction opens to the outer circumferential surface of the housing body <NUM>. An inner end portion of the first oil supply path <NUM> in the first radial direction opens to the inner circumferential surface of the housing body <NUM>. That is, the first oil supply path <NUM> extends through the housing <NUM> and opens toward the first bearing <NUM>. Oil is supplied from the outside of the housing <NUM> to the first oil supply path <NUM> through a first oil supply port 36a (see <FIG>) provided in the outer circumferential portion of the housing body <NUM>.

A plurality of the first oil supply paths <NUM> are provided. The plurality of first oil supply paths <NUM> are arranged at intervals in the first circumferential direction. The plurality of first oil supply paths <NUM> include one first oil supply path <NUM> extending linearly through the housing body <NUM> and another first oil supply path <NUM> extending through the housing body <NUM> in a crank shape in a bent state.

In the embodiment, at least one first oil supply path <NUM> is disposed at a portion located above the first center axis C1 in the vertical direction of the housing body <NUM>. Therefore, oil supplied to the first bearing <NUM> from above is likely to stably spread in the entire first bearing <NUM>.

As shown in <FIG> and <FIG>, the second oil supply path <NUM> penetrates the internal gear <NUM> and the external gear <NUM> and supplies oil to the second bearing <NUM>. The second oil supply path <NUM> includes an internal gear flow path 37a and an external gear flow path 37b.

The internal gear flow path 37a penetrates the circumferential wall of the internal gear <NUM>. In the embodiment, the internal gear flow path 37a penetrates the internal gear <NUM> in the first radial direction. The outer end portion of the internal gear flow path 37a in the first radial direction opens to the outer circumferential surface of the internal gear <NUM>. The inner end portion of the internal gear flow path 37a in the first radial direction opens to the inner circumferential surface, that is, the internal teeth 16a of the internal gear <NUM>. That is, the internal gear flow path 37a extends through the internal gear <NUM> and opens to at least the internal teeth 16a. Oil is supplied from the outside of the housing <NUM> to the internal gear flow path 37a through a second oil supply portion 37c provided in the outer circumferential portion of the internal gear <NUM>.

The external gear flow path 37b penetrates the circumferential wall of the external gear <NUM>. In the embodiment, the external gear flow path 37b penetrates the external gear <NUM> in the second radial direction. The outer end portion of the external gear flow path 37b in the second radial direction opens to the outer circumferential surface, that is, the external teeth 23a of the external gear <NUM>. The inner end portion of the external gear flow path 37b in the second radial direction opens to the inner circumferential surface of the second outer race support part 23b. That is, the external gear flow path 37b extends through the external gear <NUM> and includes a portion opening to the external teeth 23a and a portion opening to the second bearing <NUM>.

A plurality of the second oil supply paths <NUM> are provided. That is, a plurality of sets of the internal gear flow path 37a and the external gear flow path 37b are provided. In the embodiment, for example, three or more second oil supply paths <NUM> are provided. That is, three or more sets of the internal gear flow path 37a and the external gear flow path 37b are provided. The plurality of internal gear flow paths 37a are arranged at intervals in the first circumferential direction. The plurality of external gear flow paths 37b are provided at intervals in the second circumferential direction.

As shown in <FIG>, when the external gear <NUM> is disposed at a predetermined position around the first center axis C1 with respect to the internal gear <NUM>, the internal gear flow path 37a and the external gear flow path 37b face each other and communicate with each other in the first radial direction. Specifically, when the external gear <NUM> revolves in the first circumferential direction along the inner circumferential portion of the internal gear <NUM> while rotating in the second circumferential direction to be disposed at a predetermined position in the first circumferential direction, the internal gear flow path 37a and the external gear flow path 37b communicate with each other through a meshing portion between the internal teeth 16a and the external teeth 23a. Accordingly, oil in the internal gear flow path 37a flows into the external gear flow path 37b and oil in the external gear flow path 37b flows through the external gear flow path 37b inward in the second radial direction and is discharged toward the second bearing <NUM>.

The number of the internal teeth 16a of the internal gear <NUM> is twice the number of the external teeth 23a of the external gear <NUM>. Therefore, the internal gear flow path 37a and the external gear flow path 37b face each other at the predetermined position at each rotation, that is, each revolution around the first center axis C1 of the external gear <NUM>. That is, the inflow of oil from the internal gear flow path 37a to the external gear flow path 37b and the discharge of oil from the external gear flow path 37b to the second bearing <NUM> are performed at each revolution of the external gear <NUM>.

In the embodiment, at least one internal gear flow path 37a is disposed at a portion located above the first center axis C1 in the vertical direction of the internal gear <NUM>. Further, at least one external gear flow path 37b faces and communicates with the internal gear flow path 37a at a portion located above the second center axis C2 in the vertical direction of the external gear <NUM>. That is, when the internal gear flow path 37a and the external gear flow path 37b communicate with each other, oil flowing through the internal gear flow path 37a is supplied to the second bearing <NUM> from above through the external gear flow path 37b. Therefore, oil is likely to stably spread in the entire second bearing <NUM>.

Although particularly not shown, the gear has a disc shape centered around the first center axis C1. The inner circumferential surface of the gear is fitted to the outer circumferential surface of one end portion of the shaft body <NUM> in the axis direction. A surface facing one side of the gear in the axis direction contacts the surface 21e facing the other side of the first rotation body <NUM> in the axis direction. The gar is fixed to the surface 21e facing the other side of the first rotation body <NUM> in the axis direction by a screw fixing or the like. That is, the gear is provided in the first rotation body <NUM>. Further, the gear may be fixed to the shaft body <NUM>. At least a part of the gear is exposed to the outside of the housing <NUM>. The gear is connected to a cup holder driving mechanism (not shown) or the like through a connection gear (not shown). The gear outputs the rotational driving force around the first center axis C1 of the first rotation body <NUM> and the shaft body <NUM> to the outside of the reciprocating linear motion mechanism <NUM>.

In the reciprocating linear motion mechanism <NUM> of the above-described embodiment, when the rotational driving force around the first center axis C1 is transmitted from a drive source (not shown) to the shaft body <NUM> and the first rotation body <NUM>, the first rotation body <NUM> is rotated around the first center axis C1 with respect to the housing <NUM>. When the first rotation body <NUM> is rotated around the first center axis C1, the second rotation body <NUM> supported by the first rotation body <NUM> is also rotated around the first center axis C1.

At this time, since the external gear <NUM> of the second rotation body <NUM> meshes with the internal gear <NUM> of the housing <NUM>, the second rotation body <NUM> is also rotated (turned) around the second center axis C2 while being rotated (revolved) around the first center axis C1. When the reciprocating linear motion mechanism <NUM> is viewed from the axis direction, the first rotation direction T1 in which the second rotation body <NUM> is revolved around the first center axis C1 and the second rotation direction T2 in which the second rotation body <NUM> is turned around the second center axis C2 are opposite to each other.

The ram shaft connection part <NUM> connected to the second rotation body <NUM> is moved linearly in a reciprocating manner along a predetermined direction, that is, the stroke direction S in the first radial direction.

In this way, the reciprocating linear motion mechanism <NUM> of the embodiment converts the rotational driving force input to the first rotation body <NUM> into the reciprocating linear motion in the stroke direction S and outputs the result to the ram shaft connection part <NUM>. Accordingly, the punch <NUM> connected to the ram shaft connection part <NUM> through the ram shaft <NUM> is moved linearly in a reciprocating manner in the stroke direction S. Thus, it is possible to perform DI processing on the cup-shaped body W by the punch <NUM>, the die <NUM>, the cup holder <NUM>, and the like and to form the cup-shaped body W as the DI can <NUM>.

Then, according to the embodiment, the internal gear <NUM>, the external gear <NUM>, the recess <NUM>, the second bearing <NUM>, and the convex part <NUM> are disposed to overlap each other when viewed from the second radial direction. That is, since the axis positions of the internal gear <NUM>, the external gear <NUM>, the recess <NUM>, the second bearing <NUM>, and the convex part <NUM> are the same as each other, it is possible to suppress the bulkiness of the axial dimension of the reciprocating linear motion mechanism <NUM>. Thus, it is possible to suppress the outer shape of the reciprocating linear motion mechanism <NUM> in the axis direction to be small and to simplify the structure.

Since the outer shape of the reciprocating linear motion mechanism <NUM> is suppressed to be small, it is possible to reduce the power consumption of the drive motor or the like that drives the reciprocating linear motion mechanism <NUM>. Therefore, the production efficiency of the DI can <NUM> is improved.

Since the axis position of the second bearing <NUM> connecting the convex part <NUM> and the recess <NUM>, that is, the bearing <NUM> connecting the first rotation body <NUM> and the second rotation body <NUM> is the same as the axial position of the meshing portion between the internal gear <NUM> and the external gear <NUM>, it is possible to suppress an unbalanced load from acting on the bearing <NUM>. Accordingly, the load on the bearing <NUM> is reduced and the life of the parts of the bearing <NUM> can be extended.

Further, in the embodiment, the second bearing <NUM> is disposed to overlap the internal gear <NUM> and the external gear <NUM> over the entire length in the axis direction when viewed from the second radial direction.

In this case, since the internal gear <NUM> and the external gear <NUM> mesh with each other, it is possible to suppress a load acting on the second bearing <NUM> from the second radial direction from varying at each position of the second bearing <NUM> in the axis direction. Since a load on the second bearing <NUM> is equalized in the axis direction, the function of the second bearing <NUM> is maintained satisfactorily and the frequency of maintenance or the like can be reduced.

Further, in the embodiment, a part of the second bearing <NUM> and a part of the first bearing <NUM> overlap each other when viewed from the axis direction.

For example, according to the above-described configuration of the embodiment, the diameter of the first bearing <NUM> is suppressed to be small compared to a case in which the first bearing <NUM> does not overlap the second bearing <NUM> when viewed from the axis direction and disposed on the outside of the first radial direction in relation to the second bearing <NUM> unlike the embodiment. Therefore, it is possible to suppress the outer shape of the reciprocating linear motion mechanism <NUM> in the first radial direction to be small.

Further, in the embodiment, the rotational driving force around the first center axis C1 of the first rotation body <NUM> can be output to the outside of the reciprocating linear motion mechanism <NUM> through a gear. For example, the cup holder driving mechanism and the like other than the reciprocating linear motion mechanism <NUM> provided in the can body maker <NUM> can be stably operated while being synchronized with the operation of the reciprocating linear motion mechanism <NUM>.

Then, according to the embodiment, since the top wall portion 22b and the external gear <NUM> of the second rotation body <NUM> are separated from each other, at least the external gear <NUM> can be manufactured alone. The external gear <NUM> can be easily manufactured without requiring particular equipment or the like and the manufacturing cost can be reduced. Further, the external gear <NUM> and the top wall portion 22b can be separately assembled to or separated from the apparatus during the assembly of the reciprocating linear motion mechanism <NUM> or the maintenance or the like of parts of the second bearing <NUM> or the like connecting the first rotation body <NUM> and the second rotation body <NUM>. Specifically, an operator can assemble the external gear <NUM> and the top wall portion 22b to the apparatus in this order from one side of the reciprocating linear motion mechanism (device) <NUM> in the axis direction or separate the top wall portion 22b and the external gear <NUM> in this order from the device. Accordingly, each operation is simplified and the operation time is shortened. Thus, according to the embodiment, the members can be easily manufactured, the manufacturing cost can be reduced, and the workability such as assembly and maintenance is good.

Since workability such as maintenance is good, it is possible to shorten the time for stopping the operation of the can body maker <NUM> for maintenance or the like. That is, the operation time of the can body maker <NUM> can be increased and the production efficiency of the DI can <NUM> is improved.

When the operator separates the top wall portion 22b from the external gear <NUM>, it is easy to access the bearing <NUM> disposed inside the external gear <NUM> and connecting the first rotation body <NUM> and the second rotation body <NUM> from the outside of the apparatus. Since the maintenance of the bearing <NUM> is good, the function of the bearing <NUM> can be maintained satisfactorily and the life of parts can be extended.

Further, in the embodiment, the external gear <NUM> has a tubular shape centered on the second center axis C2, the top wall portion 22b blocks one opening of the external gear <NUM> in the axis direction, and the second bearing <NUM> is interposed between the inner circumferential surface of the external gear <NUM> and the outer circumferential surface of the convex part <NUM>.

In this case, it is possible to easily access the second bearing <NUM> inside the external gear <NUM> when the operator separates the top wall portion 22b from one side in the axis direction. That is, it is possible to access the second bearing <NUM> even when the external gear <NUM> is not separated from the apparatus. If necessary, the external gear <NUM> or the second bearing <NUM> can be easily separated from the apparatus. Therefore, workability such as maintenance is improved. Further, the attachment structure of the second bearing <NUM> can be simplified and the reciprocating linear motion mechanism <NUM> can have a compact configuration.

Further, in the embodiment, the pin member <NUM> is fitted to the first fitting hole 22f and the second fitting hole 23c and the bolt member <NUM> is inserted into the bolt insertion hole <NUM> and is screwed into the female screw hole 23d.

In this case, the top wall portion 22b and the external gear <NUM> can be fixed by the bolt member <NUM> while the top wall portion 22b and the external gear <NUM> are positioned around the second center axis C2 by the pin member <NUM>. Therefore, the positional accuracy of the external gear <NUM> and the ram shaft connection part <NUM> connected to the top wall portion 22b is stably ensured. Further, a force generated in the second circumferential direction between the top wall portion 22b and the external gear <NUM> during the operation or the like of the reciprocating linear motion mechanism <NUM> can be received by the pin member <NUM> which can more easily ensure rigidity than the bolt member <NUM>. Accordingly, damage or the like of the bolt member <NUM> is suppressed. The relative movement of the top wall portion 22b and the external gear <NUM> in the second circumferential direction is regulated by the pin member <NUM> and the relative movement of the top wall portion 22b and the external gear <NUM> in the axis direction is regulated by the bolt member <NUM>.

Further, in the embodiment, the top wall portion 22b includes a fitting cylinder part 22d which is fitted to the inner circumferential surface of the cylindrical external gear <NUM>.

In this case, since the external gear <NUM> and the fitting cylinder part 22d are fitted to each other, the external gear <NUM> and the top wall portion 22b are positioned in the second radial direction. Further, a force generated in the second radial direction between the top wall portion 22b and the external gear <NUM> during the operation or the like of the reciprocating linear motion mechanism <NUM> can be received by the fitting cylinder part 22d which can more easily ensure rigidity than the bolt member <NUM>. Accordingly, damage or the like the bolt member <NUM> is suppressed. The relative movement of the top wall portion 22b and the external gear <NUM> in the second radial direction is regulated by the fitting cylinder part 22d.

Then, in the embodiment, when the external gear <NUM> revolves around the first center axis C1 along the inner circumferential portion of the internal gear <NUM> while turning around the second center axis C2 to be disposed at a predetermined position around the first center axis C1 as shown in <FIG>, the internal gear flow path 37a and the external gear flow path 37b are connected through a meshing portion between the internal teeth 16a and the external teeth 23a. Accordingly, oil inside the internal gear flow path 37a flows into the external gear flow path 37b. The oil flowing into the external gear flow path 37b is discharged from the inside of the external gear flow path 37b toward the second bearing <NUM>. According to the embodiment, oil can be stably supplied to the second bearing <NUM> connecting the first rotation body <NUM> and the second rotation body <NUM> even during the operation of the can body maker <NUM>. The second bearing <NUM> is stably cooled and lubricated by oil and the performance of the second bearing <NUM> is maintained satisfactorily.

Since oil can be supplied to the second bearing <NUM> during the operation of the can body maker <NUM>, the function of the second bearing <NUM> is maintained satisfactorily and the frequency of stopping the operation of the can body maker <NUM> for the maintenance or the like of the second bearing <NUM> can be reduced. That is, the operation time of the can body maker <NUM> can be increased and the production efficiency of the DI can <NUM> is improved.

Since oil is stably supplied to the second bearing <NUM> connecting the first rotation body <NUM> and the second rotation body <NUM>, the life of parts of the second bearing <NUM> can be extended.

Further, in the embodiment, the first rotation body <NUM> and the second rotation body <NUM> are connected to each other by the convex part <NUM>, the recess <NUM>, and the second bearing <NUM> interposed therebetween, that is, the second bearing <NUM> connects the convex part <NUM> and the recess <NUM> to be relatively rotatable around the second center axis C2. Therefore, it is possible to simplify the structure of the reciprocating linear motion mechanism <NUM>.

Further, in the embodiment, the external gear flow path 37b penetrates the external gear <NUM> in the second radial direction.

In this case, the external gear flow path 37b can be formed in, for example, a simple shape such as a linear hole, the friction loss (resistance) of the oil flowing through the external gear flow path 37b can be reduced, and oil can be stably supplied to the second bearing <NUM>.

Further, in the embodiment, the internal gear <NUM>, the external gear <NUM>, the recess <NUM>, the second bearing <NUM>, and the convex part <NUM> are disposed to overlap each other when viewed from the second radial direction. That is, since the axis positions of the internal gear <NUM>, the external gear <NUM>, the recess <NUM>, the second bearing <NUM> and the convex part <NUM> are the same as each other, it is possible to easily form the second oil supply path <NUM> penetrating the internal gear <NUM> and the external gear <NUM> and opening toward the second bearing <NUM> and to suppress the flow path length of the second oil supply path <NUM> to be short.

Further, in the embodiment, the second bearing <NUM> is disposed to overlap the internal gear <NUM> and the external gear <NUM> over the entire length of the axis direction when viewed from the second radial direction.

In this case, oil is easily supplied from the second oil supply path <NUM> to the entire area of the second bearing <NUM> in the axis direction and the performance of the second bearing <NUM> becomes more stable.

Additionally, the present invention is not limited to the above-described embodiment and, for example, as described below, the configuration can be changed within the scope of the invention as defined by the claims.

The method of pressing the inner races 31a and 32a, the outer races 31b and 32b, and the spacers 31d and 32d of the first bearing <NUM> and the second bearing <NUM>, that is, the fixing means is not limited to the configurations described in the above-described embodiment.

The shape of each of the first weight part <NUM> and the second weight part <NUM> is not limited to each shape described in the above-described embodiments.

In the above-described embodiment, an example in which each of the second fitting hole 23c and the female screw hole 23d is the retaining hole recessed from the surface 23e facing one side of the external gear <NUM> in the axis direction toward the other side in the axis direction has been described, but the present invention is not limited thereto. The second fitting hole 23c may be a through-hole penetrating the external gear <NUM> in the axis direction. The female screw hole 23d may be a through-hole penetrating the external gear <NUM> in the axis direction.

In the above-described embodiment, an example in which one set of the first fitting hole 22f, the second fitting hole 23c, and the pin member <NUM> is provided has been described, but the present invention is not limited thereto. For example, a plurality of sets of the first fitting hole 22f, the second fitting hole 23c, and the pin member <NUM> may be provided at intervals in the second circumferential direction.

In the above-described embodiment, an example in which the plate-shaped top wall portion 22b is the connection part connecting the external gear <NUM> and the ram shaft connection part <NUM> has been described, but the present invention is not limited thereto. That is, the connection part of the second rotation body <NUM> may have a shape other than the top wall portion 22b, that is, a columnar shape or a block shape other than the plate shape.

In the above-described embodiment, an example in which the fitting cylinder part 22d is fitted to the inner circumferential surface of the external gear <NUM> has been described, but the present invention is not limited thereto. The fitting cylinder part 22d may be fitted to the outer circumferential surface of the external gear <NUM>. Even in this case, the same effect as described above can be obtained.

The present invention may combine the configurations described in the above-described embodiments, modifications, and the like as long as it falls within the scope of the invention as defined by the claims and may add, omit, replace, and change the configurations in other forms. Further, the present invention is not limited by the above-described embodiments and the like, but is limited only by the claims.

Claim 1:
A reciprocating linear motion mechanism (<NUM>) for a can body maker comprising:
a housing (<NUM>) including an internal gear (<NUM>) centered on a first center axis (C1);
a first rotation body (<NUM>) located inside the housing (<NUM>);
a first bearing (<NUM>) connecting the housing (<NUM>) and the first rotation body (<NUM>) to be relatively rotatable;
a convex part (<NUM>) protruding toward one side of an axis direction from a surface facing one side of the first rotation body (<NUM>) in the axis direction and centered on a second center axis (C2) parallel to the first center axis (C1);
a second rotation body (<NUM>) including an external gear (<NUM>) meshing with the internal gear (<NUM>) about the second center axis (C2) and disposed on one side of the first rotation body (<NUM>) in the axis direction;
a recess (<NUM>) which is recessed toward one side in the axis direction from a surface facing the other side of the second rotation body (<NUM>) in the axis direction and into which the convex part (<NUM>) is inserted; and
a second bearing (<NUM>) connecting the convex part (<NUM>) and the recess (<NUM>) to be relatively rotatable,
characterized in that the internal gear (<NUM>), the external gear (<NUM>), the recess (<NUM>), the second bearing (<NUM>), and the convex part (<NUM>) overlap each other when viewed from a radial direction orthogonal to the second center axis (C2).