Patent Description:
Powered agricultural balers are commonly used to bind severed hay material and other severed crop material into bales for later use, such as feed for livestock. Square balers that use discrete lengths of twine (or other strands of binding material) to bind loose material into a bale generally include a needle assembly to wrap strands of twine around each formed bale and secure the twine. Prior art balers also generally include a trip mechanism to initiate a bale tie cycle during which the needle assembly is operated to wrap a bale. For maintenance purposes, square balers are normally provided with a lockout to restrict components of the baler, including the needles and knotter mechanism, from inadvertently performing a bale tie cycle.

Conventional balers with trip devices and lockout mechanisms have various problems and limitations. For instance, the trip devices and lockout mechanisms of prior art balers are known to experience substantial wear during use. Furthermore, these known trip devices and lockout mechanisms generally require frequent maintenance and adjustment for reliable operation.

This background discussion is intended to provide information related to the present invention which is not necessarily prior art.

<CIT> discloses a baler having the features of the precharacterising portion of claim <NUM>.

The following brief summary is provided to indicate the nature of the subject matter disclosed herein. While certain aspects of the present invention are described below, the summary is not intended to limit the scope of the present invention.

Embodiments of the present invention provide a baler that does not suffer from the problems and limitations of the prior art devices set forth above.

One aspect of the present invention concerns a bale binding mechanism according to claim <NUM>. Preferred embodiments are provided in the dependent claims.

Other aspects and advantages of the present invention will be apparent from the following detailed description of the embodiments and the accompanying drawing figures.

Preferred embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:.

The drawing figures do not limit the present invention to the specific embodiments disclosed and described herein. While the drawings do not necessarily provide exact dimensions or tolerances for the illustrated components or structures, the drawings, not including any purely schematic drawings, are to scale with respect to the relationships between the components of the structures illustrated therein.

Turning to <FIG> and <FIG>, an agricultural baler <NUM> is configured to collect severed crop material (not shown) from a field and form a series of bales (not shown) from the severed crop material. The baler <NUM> preferably includes a bale binding mechanism <NUM> configured to secure strands of binding material (not shown), such as twine, around a bale of severed crop material.

Preferably, the bale binding mechanism <NUM> is provided as part of the baler <NUM>, which can be advanced along a field to collect severed crop material. In the usual manner, the baler <NUM> is generally towed by a powered tractor (not shown), or other self-powered vehicle, so as to be advanced in a forward direction F along a windrow of severed crop material. As the baler <NUM> is advanced, a baler pickup device D of the baler <NUM> collects the windrow and directs the windrow material into a baling chamber <NUM> defined at least in part by a baler chassis <NUM>.

The bale binding mechanism <NUM> preferably includes a knotter mechanism <NUM>, a needle assembly <NUM>, a clutch <NUM>, and a trip mechanism <NUM> (see <FIG>). As will be described further, the trip mechanism <NUM> preferably provides a lockout condition in which the baler <NUM> is restricted from performing a bale tie cycle (e.g., to facilitate baler maintenance).

The baler chassis <NUM> is configured to support the baler pickup device D, the bale binding mechanism <NUM>, and other operating components. The baler chassis <NUM> includes, among other things, a baler frame <NUM> that presents the baling chamber <NUM>. The baler frame <NUM> is preferably conventional and includes a series of fore-and-aft extending frame members (not shown) that at least partly define the baling chamber <NUM> and direct severed crop material through the baling chamber <NUM> as the material is formed into bales (not shown). In the illustrated embodiment, the baler frame <NUM> also operably supports the knotter mechanism <NUM>, needle assembly <NUM>, and trip mechanism <NUM>.

As a bale is formed within the baling chamber <NUM>, strands of twine (not shown) are extended and eventually secured around the bale. In the usual manner, bales are generally formed in a rearward direction and directed rearwardly out of the baler <NUM>. The baling chamber <NUM> extends fore-and-aft to permit bales to be formed and advanced rearwardly.

Turning to <FIG>, the knotter mechanism <NUM> and needle assembly <NUM> are configured to be driven by a drive sprocket <NUM> for binding bales in the baling chamber <NUM>. The drive sprocket <NUM> is powered by a chain drive (not shown) and includes a cylindrical skirt 38a (see <FIG>) and a lobe 38b (see <FIG>) operable to be engaged by the clutch <NUM>.

In the usual manner, the knotter mechanism <NUM> includes a drive shaft <NUM> and multiple knotter head assemblies <NUM> (see <FIG>). The knotter head assemblies <NUM> are powered by the drive shaft <NUM> and cooperate with the needle assembly <NUM> to form at least one knot in respective strands of twine during a bale tie cycle. The drive sprocket <NUM> is journaled on the drive shaft <NUM> and is configured to spin relative to the drive shaft <NUM> when the baler <NUM> is not performing a bale tie cycle.

The illustrated needle assembly <NUM> includes a cam wheel <NUM>, crank arm <NUM>, rod <NUM>, needle frame <NUM>, and needles <NUM>. The cam wheel <NUM> and the crank arm <NUM> are attached to and rotate with the drive shaft <NUM> of the knotter mechanism <NUM>. In particular, the cam wheel <NUM> and crank arm <NUM> are each configured to rotate a single revolution with the drive shaft <NUM> during a bale tie cycle. As described below, the bale tie cycle is initiated when the clutch <NUM> is engaged.

The needles <NUM> are mounted on the needle frame <NUM> and are each associated with a respective strand of twine (see <FIG>). Each needle <NUM> is configured to advance twine vertically along an end of the bale (see <FIG>). The needle <NUM> presents a distal needle end <NUM> that receives and supports the twine during operation.

The needles <NUM> are shiftable relative to the baling chamber <NUM> during a bale tie cycle to bind a bale. In the depicted embodiment, the needles <NUM> are shiftable upwardly into the baling chamber <NUM> during an advancement stroke of the bale tie cycle to advance strands of twine upwardly along an end of the bale. The needles <NUM> position the strands of twine so that the knotter mechanism <NUM> can secure the twine around the bale. The needles <NUM> are also shiftable downwardly out of the baling chamber <NUM> during a return stroke of the bale tie cycle to permit formation of the next bale.

Although the illustrated embodiment references upward and downward directions associated with the needles <NUM> and other baler components, it will be appreciated that at least some aspects the present invention broadly cover alternative orientations and movements of the baler components. For instance, it is within the scope of at least some aspects of the present invention for the needle assembly to be alternatively positioned relative to the baling chamber (e.g., above the chamber).

Turning to <FIG> and <FIG>, the clutch <NUM> is operable to initiate a bale tie cycle and transmit driving power from the drive shaft <NUM> to the needle assembly <NUM>. The depicted clutch <NUM> includes a clutch body <NUM> and a roller <NUM> that is rotatably supported by the clutch body <NUM>. The clutch body <NUM> is pivotally mounted relative to the cam wheel <NUM>. This pivotal mounting permits rotation of the clutch <NUM> between an engaged condition (not shown), in which the clutch <NUM> drivingly interconnects the drive shaft <NUM> and the needle assembly <NUM>, and a disengaged condition (see <FIG> and <FIG>), in which the clutch <NUM> prevents the drive shaft <NUM> from driving the needle assembly <NUM>.

In the engaged condition (not shown), the roller <NUM> is shifted into engagement with the skirt 38a to contact the lobe 38b. With the roller <NUM> and lobe 38b engaged with each other, the clutch <NUM> is configured to transmit driving torque from the sprocket <NUM> to the cam wheel <NUM>. In turn, the driving torque is transmitted to the knotter mechanism <NUM> and the needle assembly <NUM> for performing a bale tie cycle.

In the disengaged condition, the clutch <NUM> is rotated from the engaged condition so that the roller <NUM> is spaced radially inwardly from the skirt 38a (see <FIG> and <FIG>). With the clutch <NUM> disengaged, the clutch <NUM> permits the drive sprocket <NUM> to spin freely relative to the drive shaft <NUM>.

Turning to <FIG>, the trip mechanism <NUM> is operable to control the size of the bale produced by the bale binding mechanism <NUM>. More specifically, the illustrated trip mechanism <NUM> is preferably adjustable so that the operator can set a desired bale length. The trip mechanism <NUM> preferably includes, among other things, a support <NUM>, a drive <NUM>, a trip cam <NUM>, a trip arm <NUM>, a lockout device <NUM>, and a bale size adjuster <NUM> (see <FIG>).

The depicted support <NUM> is configured to position various components of the trip mechanism <NUM> for trip mechanism operation. The support <NUM> includes a frame <NUM> with upstanding walls 72a,72b and a sleeve <NUM> that interconnects the walls 72a,72b.

As is customary, the drive <NUM> is operable to power the trip cam <NUM> for producing the desired bale length. The illustrated drive <NUM> preferably includes a powered star wheel <NUM>, a drive wheel <NUM>, and a shaft <NUM> that drivingly connects the wheels <NUM>,<NUM> (see <FIG>). The star wheel <NUM> is conventional and includes large teeth to engage the bale as the bale passes along the baling chamber <NUM>.

The drive wheel <NUM> is operable to shift the trip cam <NUM> during baler operation. The drive wheel <NUM> preferably comprises a metering gear with a series of gear teeth <NUM>. In the metering condition, the teeth <NUM> of the drive wheel <NUM> engage a toothed surface of the trip cam <NUM> (see <FIG>). As a bale passes along the baling chamber <NUM>, the star wheel <NUM> is rotated by the bale and causes the drive wheel <NUM> to rotate. As explained below, rotation of the drive wheel <NUM> produces corresponding upward movement of the trip cam <NUM>.

The trip arm <NUM> is shiftable to cause engagement and disengagement of the clutch <NUM>. As will be explained further, the trip arm <NUM> is shiftable with the trip cam <NUM> between a trip condition associated with engagement of the clutch <NUM> and a metering condition associated with disengagement of the clutch <NUM>.

The trip arm <NUM> includes a unitary body <NUM> pivotally attached relative to the chassis <NUM> at a pivot joint <NUM>, and a cam roller <NUM> rotatably supported by the body <NUM> (see <FIG>). The body <NUM> includes arm segments 84a,84b that extend away from the pivot joint <NUM> (see <FIG>).

In the depicted embodiment, the arm segment 84a is operable as a pawl to removably contact the clutch <NUM> in a clutch contact position and hold the clutch <NUM> in the disengaged clutch condition (see <FIG>). As noted above, the disengaged condition of the clutch <NUM> preferably corresponds to the metering condition of the trip arm <NUM>.

The arm segment 84a is also shiftable out of contact with the clutch <NUM> (see <FIG>) so that the clutch <NUM> is allowed to shift into the engaged clutch condition. Again, engagement of the clutch <NUM> preferably corresponds to the trip condition of the trip arm <NUM>.

A spring <NUM> is attached to the trip arm <NUM> and urges the trip arm <NUM> out of the clutch contact position to permit disengagement of the clutch <NUM> (see <FIG>). During the bale tie cycle, the trip arm <NUM> is returned to the clutch contact position by the cam wheel <NUM>, which engages the cam roller <NUM> to pivot the trip arm <NUM> back to the clutch contact position.

As noted above, the trip cam <NUM> is shiftable between the trip condition associated with engagement of the clutch <NUM> and the metering condition associated with disengagement of the clutch <NUM>. The trip cam <NUM> is preferably shiftable from the metering condition to the trip condition to engage the clutch <NUM> when the bale is formed to a predetermined size (e.g., a predetermined bale length).

In the illustrated embodiment, the trip cam <NUM> includes a cam frame <NUM> with a pair of legs <NUM> and a cam body <NUM> extending between ends of the legs <NUM> (see <FIG>). The cam frame <NUM> and cam body <NUM> cooperatively form an opening <NUM> that operably receives the drive wheel <NUM>. The legs <NUM> of the cam frame <NUM> are pivotally attached to the arm segment 84b at a pivot joint <NUM> (see <FIG> and <FIG>). For at least some aspects of the present invention, the cam frame could be alternatively constructed and/or positioned for supporting the cam body.

In the depicted embodiment, the cam body <NUM> preferably presents a slotted opening <NUM>, in the form of a curved, elongated slot, to removably receive the lockout device <NUM>. The cam body <NUM> also presents a driven edge surface <NUM> extending along the slotted opening <NUM>. The driven edge surface <NUM> preferably comprises a toothed surface that is curved and defines a curved path P (see <FIG>). The trip cam <NUM> is operable to be driven by the drive wheel <NUM> to travel along the curved path P while in the metering condition. In particular, the drive wheel <NUM> engages the driven edge surface <NUM> in the metering condition, such that rotation of the drive wheel <NUM> causes the cam body <NUM> to swing along and the driven surface <NUM> to advance along the path P.

The cam body <NUM> further presents an offset surface <NUM> that is at least partly offset from the driven surface <NUM> along the transverse direction and spaced from the driven surface <NUM> along the path P (see <FIG>). The offset surface <NUM> defines a relief opening <NUM> that at least partly receives the drive wheel <NUM> in the trip condition (see <FIG>). The relief opening <NUM> is preferably positioned so as to be spaced from the slotted opening <NUM>.

For at least some aspects of the present invention, the cam body could be alternatively configured to facilitate trip mechanism operation. For instance, the cam body could present an alternative opening for engagement with the lockout device (e.g., a single opening having a complemental shape to the lockout device to snugly receive the device or a portion of the device (such as a circular opening receiving a similarly shaped pin)). Yet further, it is within of the scope of some aspects of the present invention for the trip cam to include another type of connection device for providing a suitable connection with the lockout device.

Alternative embodiments of the cam body may also include an alternative relief opening for cooperating with the drive wheel to provide the trip condition. In still other embodiments, consistent with some aspects of the present invention, the trip cam could have structure other than the depicted relief opening so that the trip cam facilitates the trip condition.

During use, the driven surface <NUM> of the trip cam <NUM> is preferably engaged by the drive wheel <NUM> in the metering condition to drive the trip cam <NUM> from a starting position (see <FIG> and <FIG>) toward the relief opening <NUM>. The drive wheel <NUM> is driven by the star wheel <NUM> as the star wheel <NUM> is spun (see <FIG>) by a bale advancing along the baling chamber <NUM>. Rotation of the drive wheel <NUM> produces corresponding upward movement of the trip cam <NUM>.

The starting position of the trip cam <NUM> is preferably set by the bale size adjuster <NUM>. The adjuster <NUM> is removably inserted through a slot <NUM> for attachment to the upstanding wall 72a. The depicted adjuster <NUM> is preferably vertically adjustable along the slot <NUM> to change the location of the starting position along the upstanding wall 72a.

The adjuster <NUM> is preferably located in a relatively lower starting position along the slot <NUM> to produce a relatively longer bale length. Conversely, the adjuster <NUM> is preferably located in a relatively higher starting position along the slot <NUM> to produce a relatively shorter bale length.

During use, the drive wheel <NUM> is disengaged from the driven surface <NUM> when the trip cam <NUM> shifts from the metering condition to the trip condition. The trip cam <NUM> is shiftable in a direction transverse to the path P when shifting between the metering condition and the trip condition. For instance, when the trip cam <NUM> shifts to the trip condition so that the drive wheel <NUM> is received by the relief opening <NUM>, the trip cam <NUM> moves in a forward direction relative to the baler chassis <NUM>. As noted above, with the trip cam <NUM> shifted to the trip condition, the trip arm <NUM> is moved out of contact with the clutch <NUM> and permits engagement of the clutch <NUM> to start a bale tie cycle.

As the bale tie cycle is performed, the cam wheel <NUM> moves the trip arm <NUM> back to the clutch contact position. Such movement of the trip arm <NUM> shifts the trip cam <NUM> along the transverse direction so that the trip cam <NUM> can return to the metering condition. Preferably, the trip cam <NUM> is shifted rearwardly to permit the drive wheel <NUM> to be moved out of the relief opening <NUM> and into a position along the driven surface <NUM>. Preferably, a spring <NUM> urges the trip cam <NUM> to return along the path P to the starting position associated with the metering condition.

The lockout device <NUM> is preferably configured for selectively restricting the baler <NUM> from performing a bale tie cycle. When the lockout device <NUM> is engaged with the trip cam <NUM> in the lockout condition, the lockout device <NUM> and the trip cam <NUM> cooperatively restrict the trip mechanism <NUM> from shifting into the trip condition. That is, in the lockout condition, the lockout device <NUM> and trip mechanism <NUM> cooperatively restrict the baler <NUM> from inadvertently performing a bale tie cycle (e.g., to facilitate baler maintenance).

The illustrated lockout device <NUM> is preferably spring-loaded and includes a lockout pin <NUM>, a spring <NUM>, washers <NUM>, and cotter pins <NUM> (see <FIG>). The lockout pin <NUM> includes opposite pin sections <NUM>,<NUM> joined by a bight <NUM> (see <FIG>). The pin section <NUM> is preferably slidably received by an opening <NUM> in the support <NUM>. The spring <NUM> is received on the pin section <NUM> between and endmost washer <NUM> and the upstanding wall 72a. The spring <NUM> preferably urges the pin section <NUM> toward the upstanding wall 72a.

It is within the ambit of the present invention for the lockout device to be alternatively constructed for selective engagement with the trip cam. In alternative embodiments, the lockout device could include an alternative structure for insertion into the cam body. An alternative lockout device may also include a connection structure that engages the cam body (or another part of the trip cam) without being inserted into or through the trip cam. It is also within the scope of at least some aspects of the present invention for the lockout device to be alternatively shiftably supported relative to the trip cam <NUM>, or include multiple components (e.g., pin sections) configured to engage the trip cam.

The lockout pin <NUM> is operable to be removably secured in an engaged position associated with engagement with the trip cam <NUM>, and a disengaged position, in which the lockout pin <NUM> is disengaged from the trip cam <NUM>.

In the disengaged position, the lockout pin <NUM> is preferably spaced from the trip cam <NUM>. Preferably, the pin section <NUM> of the lockout pin <NUM> is removably secured in an opening <NUM> in the upstanding wall 72a (see <FIG> and <FIG>). The spring <NUM> preferably urges the pin section <NUM> into the opening <NUM> when in the disengaged position. However, the spring <NUM> also preferably permits shifting of the lockout pin <NUM> so that the pin section <NUM> can be selectively removed from the opening <NUM> (e.g., for engaging the lockout pin <NUM> with the trip cam <NUM>).

In the engaged position, the pin section <NUM> of the lockout pin <NUM> preferably extends through the slotted opening <NUM> (see <FIG>) and into an opening <NUM> (see <FIG>) in the upstanding wall 72a. Securement of the pin section <NUM> through the slotted opening <NUM> is operable to restrict or limit movement of the trip cam <NUM> out of the metering condition. When secured in the slotted opening <NUM>, the lockout pin <NUM> and trip cam <NUM> are slidably interconnected such that the trip cam <NUM> is permitted to swing along the path P relative to the lockout pin <NUM> (while being retained in the metering condition) but prevented from shifting into the trip condition. In particular, with the lockout pin <NUM> slidably received in the slotted opening <NUM>, relative movement between the trip cam <NUM> and lockout pin <NUM> along the path P is permitted, but the trip cam <NUM> is maintained in the metering condition.

The spring <NUM> preferably urges the pin section <NUM> of the lockout pin <NUM> through the slotted opening <NUM> and into the opening <NUM> when in the engaged position. However, the spring <NUM> also preferably permits shifting of the lockout pin <NUM> so that the pin section <NUM> can be selectively removed from the opening <NUM> (e.g., to remove the lockout pin <NUM> from the slotted opening <NUM> so that the lockout pin <NUM> can be secured in the disengaged position).

It is within the ambit of some aspects of the present invention for the lockout device to be alternatively configured for engagement with the trip cam or another part of the trip mechanism (e.g., to provide suitable lockout operation). As noted above, alternative embodiments of the lockout device may include an alternative structure for alternative shifting engagement with the trip cam. For instance, the lockout device could have an alternative complemental shape to engage the trip cam. Certain aspects of the present invention contemplate a lockout device defining an opening in which a portion of the trip cam is received.

In operation, the baler <NUM> is configured to form bales in the baling chamber <NUM> and bind each bale during a respective bale tie cycle. A new bale is formed, starting after the previous bale tie cycle, by adding severed crop material into the baling chamber <NUM>. The drive wheel <NUM> is spun as crop material is advanced along the baling chamber <NUM>, which produces corresponding upward movement of the trip cam <NUM> from the starting position toward the relief opening <NUM>.

As the drive wheel <NUM> advances beyond the driven surface <NUM> into the relief opening <NUM>, the trip cam <NUM> shifts from the metering condition to the trip condition. With the trip cam <NUM> shifted to the trip condition, the trip arm <NUM> is moved out of contact with the clutch <NUM> and permits engagement of the clutch <NUM> to start a bale tie cycle.

Once the bale tie cycle is initiated, the needles <NUM> are shiftable upwardly into the baling chamber <NUM> during an advancement stroke of the bale tie cycle to advance strands of twine upwardly along an end of the bale. The needles <NUM> are then shiftable downwardly out of the baling chamber <NUM> during a return stroke of the bale tie cycle to permit formation of the next bale. During normal baling operations, the lockout device <NUM> is shifted out of the lockout condition.

To restrict the baler <NUM> from performing a bale tie cycle, the lockout device <NUM> may be selectively moved into the lockout condition, which is preferable for facilitating baler maintenance. In the lockout condition, the lockout device <NUM> preferably engages the trip cam <NUM> to restrict movement into the trip condition. In particular, the pin section <NUM> of the lockout pin <NUM> is positioned to extend through the slotted opening <NUM> (see <FIG>) and into an opening <NUM> (see <FIG>) in the upstanding wall 72a. With respect to the illustrated embodiment, the lockout device <NUM> assuredly prevents initiation of a bale tie cycle but allows flexibility as to when the needle assembly <NUM> is locked out. Preferably, the lockout device <NUM> can be engaged in the lockout condition at any point during baling prior to initiation of the bale tie cycle (i.e., at essentially any point within the metering condition of the trip cam <NUM>).

In a similar manner, the lockout device <NUM> may be selectively moved out of the lockout condition to a disengaged position, so that the baler <NUM> is again configured for normal baling operation. In the disengaged position, the lockout device <NUM> is disengaged from the trip cam <NUM>. Preferably, the pin section <NUM> of the lockout pin <NUM> is removably secured in the opening <NUM> in the upstanding wall 72a (see <FIG> and <FIG>).

Although the above description presents features of preferred embodiments of the present invention, other preferred embodiments may also be created in keeping with the scope of the claims.

Claim 1:
A baler (<NUM>) for forming crop material into a bale, said baler (<NUM>) comprising:
a chassis (<NUM>) presenting a baling chamber (<NUM>) in which the bale is formed; and
a bale binding mechanism (<NUM>) configured to wrap twine around the bale, said bale
binding mechanism (<NUM>) including-
a baling needle (<NUM>) shiftable relative to the baling chamber (<NUM>), with the baling needle (<NUM>) being shiftable to advance twine along an end of the bale,
a drive shaft (<NUM>) supported by the chassis (<NUM>) to power the baling needle (<NUM>),
a clutch (<NUM>) shiftable between an engaged condition in which the clutch (<NUM>) drivingly interconnects the drive shaft (<NUM>) and the baling needle (<NUM>), and
a disengaged condition in which the clutch (<NUM>) prevents the drive shaft (<NUM>) from driving the baling needle (<NUM>), and
a trip mechanism (<NUM>) including a trip cam (<NUM>), a drive wheel (<NUM>), and a lockout device (<NUM>),
said trip cam (<NUM>) being shiftable between a trip condition associated with engagement of the clutch (<NUM>) and a metering condition associated with disengagement of the clutch (<NUM>);
said drive wheel (<NUM>) being operable to shift the trip cam (<NUM>) when in the metering condition,
said trip cam (<NUM>) being shiftable from the metering condition to the trip condition to engage the clutch (<NUM>) when the bale is formed to a desired size,
said lockout device (<NUM>) removably engaging the trip cam (<NUM>) to restrict the trip cam (<NUM>) from shifting into the trip condition
said trip cam (<NUM>) presenting a cam opening (<NUM>) that removably receives the lockout device (<NUM>) for engagement therewith, characterised by
said trip cam (<NUM>) presenting a driven surface (<NUM>) extending along the cam opening (<NUM>),
said driven surface (<NUM>) being engaged by the drive wheel (<NUM>) in the metering condition, and
said drive wheel (<NUM>) being disengaged from the driven surface (<NUM>) when the trip cam (<NUM>) is in the trip condition.