GB2198344A - Automatic tension spring mounting device - Google Patents

Abstract

An automatic tension spring mounting device (60) used for spreading a pad receive member (5) onto a seat frame in a seat for a vehicle such as an automobile is provided with a plurality of guide means (65) respectively located so as to correspond to engagement portions in the seat frame and adapted to be able to restrict tension springs (S) each having end hooks in the two ends thereof in the peripheral and longitudinal directions thereof. When mounting the tension springs, the end hooks of the tension springs can be guided into the seat frame engagement portions by the guide means. <IMAGE>

Description

AUTOMATIC TENSION SPRING MOUNTING DEVICE The present invention relates to a tension spring takeout device in an apparatus for automatically mounting a plurality of tension springs which are used to spread a pad receive member over a seat frame in an automotive seat.

In the prior art, as a typical example of cushion structures for use in vehicle seat, there is known such a cushion structure as disclosed in Japanese Utility Model Publication No 5,882 of 1972.

Specifically, in the disclosed cushion structure, as shown in Fig 1, a plurality of wires (3) are stretched between two side members (2a), (2b) and a separation member (4) is inserted between the thus stretched wires (3) to form a so-called screen-shaped pad receive member (5); and, the pad receive member (5) is then resiliently spread between the front and rear frames (la), (lb) of a seat frame (1) on the two sides thereof by means of tension springs S, which resiliency can provide a comfortable cushion effect.

The illustrated seat frame (1) is a so-called bench seat frame including two pad receive members (5) which are spread or located symmetrically in the right and left portions thereof. In this seat frame (1), in consideration of resilient touch provided when an occupant is seated thereon, the tension springs are mounted at different intervals.

To mount the tension springs S of each of the pad receive members (5) in the seata frame (1), one of end hooks formed symmetrically on the two ends of the tension spring S is secured to a side element of the pad receive member (5), the other end hook is inserted into an engagement hole (6) formed in the seat frame (1); and, in this manner, a required number of tension springs S are secured sequentially to either of the front and rear frames (la), (lb) of the seat frame (1) from one side thereof, and then similarly a required number of tension springs S are secured to the other of the front and rear frames.

The above-mentioned operation for mounting the tension springs S of the pad receive members (5) in the seat frame (1) has been performed by means of a manual operation, for the most part, in the prior art. This manual operation has required much labour and has not been efficient.

In order to avoid such disadvantages found in the conventional manual mounting operation, recently, there has been proposed an automatic tension spring mounting apparatus which is capable of automatically mounting tension springs using an industrial robot.

However, since the conventional automatic tension spring mounting apparatus of this type is arranged such that the tension springs are supplied and mounted one by one to their mounting portions, it requires almost the same mounting time as in the manual operation, and, therefore, the working efficiency of the automatic apparatus cannot be improved so greatly.

The present invention aims at eliminating the drawbacks found in the above-mentioned conventional automatic tension spring mounting apparatus.

Accordingly, it is an object of the invention to provide a tension spring takeout device which is capable of taking out and mounting a predetermined number of tension springs simultaneously so as to be able to reduce the time for mounting the tension springs.

According to a first aspect of the present invention there is provided apparatus for automatically mounting a predetermined number of tension springs on respective mounting portions of frame members in a seat frame, the apparatus comprising a stock mechanism for sequentially separating a large number of tension springs from one another, arranging said tension springs in line, and stocking said tension springs therein; a takeout mechanism including a predetermined number of takeout means located in said stock mechanism so as to correspond to the required mounting intervals of said tension springs on said frame members, and operable such that a predetermined number of tension springs can be pushed out simultaneously; and, a transfer device located in a receiving portion relative to said takeout mechanism and operable such that it can catch said tension springs pushed out by the takeout mechanism, transfer said tension springs to the mounting portions of said frame members, and mount said tension springs on said mounting portions of said frame members.

Thus, apparatus according to the present invention comprises a supply shute serving as a stock mechanism into which tension springs discharged from a part feeder provided with a separation mechanism to separate the tension springs from one another are successively supplied and stocked in line; a takeout mechanism which includes a predetermined number of takeout means formed in the successive supply portion or horizontal portion of the supply shute and respectively located correspondingly to the mounting distances of the tension springs with respect to a seat frame and which is operable such that a predetermined number of tension springs can be pushed out simultaneously; and, a transfer device which catches the tension springs pushed out from the takeout mechanism and transfers them to the mounting portion of the seat frame for mounting them thereto.

Accordingly, the tension springs discharged from the part feeder are delivered to the horizontal portion of the supply shute serving as the stock mechanism, and are arranged in line in a transverse direction for stocking.

And, when the tension springs are stocked in this manner, then the takeout mechanism is operated so that a predetermined number of tension springs are pushed out simultaneously, that is, the predetermined number of tension springs are simultaneously taken out at predetermined intervals by the takeout means. When the predetermined number of tension springs are taken out in this manner, then the transfer device is operated so that the tension springs taken out by the takeout mechanism are simultaneously caught and are then transferred and mounted to the mounting portion of the seat frame.

According to a second aspect of the present invention there is provided a method of automatically mounting a predetermined number of tension springs on frame members in a seat frame, the method comprising separating a large number of tension springs from one another and arranging them side by side in a line, selecting a pre-determined number of the tension springs so arranged and presenting each of the selected springs to a transfer device which is operable to transfer the selected springs to the seat frame and mount the springs in the required positions on the frame members of the seat frame.

For this reason, according to the invention, the time necessary to mount the tension springs can be reduced when compared with the prior art devices, resulting in the improved efficiency of the mounting operation.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig 1 is a plan view of a seat frame of an automotive seat including a pair of pad receive members each of which is spread by tension springs; Fig 2 is a front view of an automatic tension spring mounting device into which the present invention is applied; Fig 3 is a perspective view of a part feeder; Fig 4 is a plan view of the above part feeder; Fig 5 is a perspective view of a tension spring takeout device constructed in accordance with the invention; Fig 6 is a longitudinal side section view of the tension spring takeout device of the invention; Fig 7 is a longitudinal front section view of a takeout mechanism portion of the tension spring takeout device of the invention.

Fig 8 is a longitudinal front section view of the above takeout mechanism portion, illustrating a state in which the tension springs have been taken out; Fig 9 is an explanatory view to illustrate how the end hook of the tension spring is restricted in the peripheral direction thereof when the tension spring is caught; Fig 10 is a perspective view of a portion of an automatic tension spring mounting device located downstream of the present tension spring takeout device; Fig 11 is a longitudinal side section view of the portion shown in Fig 10; and, Fig 12 is an explanatory view to illustrate how the end hook of the tension spring is restricted in the peripheral direction thereof when the tension spring is mounted.

In Fig 2, reference numeral (11) designates an entire automatic tension spring mounting device which includes a pair of pad receive members (5) both spread over a seat frame (1) as shown in Fig 1, and (12) represents a part feeder to supply tension springs S. The part feeder (12) is provided with a separation mechanism for the tension springs S so that a large number of tension springs S input to the part feeder (13) can be separated from one another and sent out into a linear feeder (13).

Figs 3 and 4 are perspective and plan views of the above-mentioned part feeder (12), respectively. The part feeder (12) is formed in the internal peripheral surface thereof with a feed passage (14) which extends spirally from the bottom portion thereof to the upper surface opening portion thereof, so that, when the part feeder (12) is vibrated, then the tension springs S can be moved through the feed passage (14) along the inner side wall thereof. In the feed passage (14), there are formed two narrow-width portions (15) each of which has a width substantially equal to the outside diameter of the tension spring S.Also, the feed passage (14) is equipped with two inclined projections (16) extending over the inside wall of the part feeder (12) and the upper surface of the feed passage (14), each of the projections (16) providing a level difference which is slightly greater than the outside diameter of the tension spring S.

When a large number of tension springs S are input into the thus constructed part feeder (12) and the part feeder (12) is caused to vibrate, then the tension springs S can be transferred successively in the longitudinal direction thereof along the feed passage (14) from the bottom portion of the part feeder (12) toward the upper surface opening portion of the part feeder (12). Due to the fact that the width of each of the narrow-width portions (15) is defined to be equal to the width of 1 piece of tension spring S, when the tension spings S pass through the narrow-width portion (15), the tension springs S that overrun the narrow-width portion (15) are caused to fall down onto the bottom portion of the part feeder (12), with the result that the tension springs S can be arranged in a line.

Then, when the thus lined tensions springs S pass through the projection (16), the end hooks Sf of the two adjacent tension springs S can be disentangled from each other, when they are entangled. In other words, when the two adjacent tension springs S with the respective end hooks Sf thereof being entangled with each other override and pass through the projection (16), the tension spring S that has passed earlier than the other is caused to shift with respect to the following tension spring S due to the level difference of the projection (16), so that the respective end hooks Sf of the two tension springs S are separated from each other, that is, the entanglement of the two tension springs S is removed.

Such separation of the end hooks Sf of the tension springs S is carried out at the two projections (16). The thus separated tension springs S are then abutted against an abutment guide member (17) provided in the end portion of the feed passage (14) and are rotated along the arcshaped surface of the abutment guide member (17) to turn their directions to the outside. As a result of this, the tension springs S are finally separated from one another and the direction-turned tension springs S are then caused to fall down from the end portion of the feed passage (14) into a box (20) located correspondingly to the feed passage (14) end portion, when one end hook Sf of the tension spring S is brought into engagement with a rail member (21a).However, in case of the tension springs S with their end hooks Sf remaining still entangled with each other, since the end hooks Sf are not to be engaged with the rail member (21a), the tension springs S drop from a drop portion (22) down to the bottom portion of a receive portion (12a) of the part feeder (12) and are then moved back into the part feeder (12).

And, the tension spring S with one end hook Sf engaged with the rail member (21) is moved on along the rail member (21a) due to the vibrations of the part feeder (12), and, when it goes beyond the drop portion (22), the other end hook Sf thereof is also brought into engagement with the rail member (21b). Thus, the tension spring S, with the two end hooks Sf engaged with the two rail members (21a) and (21b), is then sent out onto a pair of parallel guides (13a) of the linear feeder (13) which are located in the extended directions of the rail members (21a) and (21b), respectively.

Referring now to Fig 5, there are shown a stock mechanism, a takeout mechanism (40), and a transfer device (47).

The tension spring S that is sent out onto the linear feeder from the part feeder (12) in the above-mentioned manner is then delivered by means of the vibratory movements of the linear feeder to a supply shute (30) located correspondingly to the front portion of the parallel guides (13a). Further, the tension spring S delivered to the supply shute (30) is once stocked by a delivery device (31) disposed midway in an inclined portion of the supply shute (30). When the number of the tension springs S stocked there reaches a predetermined number, this is sensed by a sensor (32) to thereby put the delivery device (31) into operation, with the result that a predetermined number of tension springs S (4 pieces in this embodiment) are allowed to fall down.

When the tension springs S are dropped down in this manner, then a cylinder (34a) is put into operation by means of sensing of an adjacent switch (33a), with the result that a pushout body (34) pushes out the tension springs S to a horizontal portion, that is, a successive supply portion of the supply shute (30) serving as a stock mechanism and thus the tension springs S are successively supplied and arranged in line in a transverse direction.

The horizontal portion (35) of the supply shute (30) is composed of a pair of L-shaped-section rail members (35a), (35b) respectively fixed to a base (36). One rail member (35a) is formed higher and the other rail member (35b) is formed lower, which provides a difference in level between them. For this reason, the tension springs S are stocked in line in the transverse direction at a predetermined angle of inclination since the respective end hooks Sf thereof are engaged in higher and lower positions.

The horizontal portions (35) of the supply shute (30) is equipped with the takeout mechanism (40) which serves to take out a predetermined number of tension springs S.

Referring now to Fig 6, there is shown a longitudinal side section view of the takeout mechanism (40).

Description will be given of the construction of the takeout mechanism (40) in connection with Figs 5 and 6. A support bracket (41) is fixed to the both side surfaces of the base (36) in such a manner that it extends across the two base side surfaces downwardly and transversely of the base (36). A cylinder (42) is perpendicularly fixed to the support bracket (41) such that the cylinder (42) is located just below the horizontal portion (35) of the supply shute (30). The cylinder (42) includes a cylinder rod (42a) to the upper end of which is connected a support member (43) having a U-shaped section and also having a length substantially equal to that of the horizontal portion (35) of the supply shute (30). A predetermined number of takeout means (44), [ (44a), (44b), (44c), (44d), (44e), (44f) ] are mounted perpendicularly to the support member (43).

Each of the takeout means (44) comprises a pair of claw-piece-shaped members (441) (442) respectively located along the respective inside surfaces of the two rail members (35a)(35b) of the horizontal portion (35) of the supply shute (30) in different levels so as to correspond to the two rail members (35a)(35b). The mounting distances between the takeout means (44) are made to correspond to the mounting intervals of the tension springs S in the seat frame (1), that is, the intervals between the engagement holes (6) respectively expressed as a, b, c (Fig 1).In other words, in the illustrated embodiment, the first takeout means (44a), the third takeout means (44c), the fifth takeout means (44e) and the sixth takeout means (44f) are equal in intervals to the sixth takeout means (44f), the fourth takeout means (44d), the second takeout means (44b) and the first takeout means (44a), respectively, so that they correspond to the intervals a, b, c of the engagement holes (6) in the seat frame (1), respectively (see Fig 7).

Also, each of the takeout means (44) is formed in the tip end thereof with a cutaway inclined recess (45) the deepest cutaway portion of which is made to correspond accurately to the position of its associated engagement hole (6) in the seat frame (1).

Further, on one side of the horizontal portion (35) of the supply shute (30), there are provided a predetermined number of direction restricting means (46) respectively corresponding to the takeout means (44). Each of the direction restricting means (46) comprises a pair of opposing wall members (46a)(46b) providing a clearance therebetween which is made to correspond to the inclined recess (45) in each of the takeout means (44). The clearance is formed open both in the upper and lower end portions and the central distance thereof is slightly greater than the diameter of the tension spring S.

In the takeout mechanism (40) constructed in the above-mentioned manner, when the tension springs S are stocked in the horizontal portion (35) of the supply shute (30), then the adjacent switch (33b) senses this to thereby put the cylinder (42) into operation. As a result of this, the takeout means (44) are caused to move up vertically and the two end hooks Sf of each of the tension springs S are brought into engagement with the cutaway deepest portion of the inclined recess (45), whereby a plurality of tension springs S are pushed up from the horizontal portion (35) of the supply shute (30), that is, taken out simultaneously (Fig 8).Although the tension springs S may individually have different outside diameters, during the takeout operation, due to the fact that the cutaway deepest portion of the inclined recess (45) in the takeout means (44) is made to correspond accurately to the position of the engagement hole (6) in the seat frame (1), the tension springs S can be taken out in such a manner that the end hooks Sf thereof are rectified so as to correspond to any of the intervals a, b, c of the engagement holes (6) in the seat frame (1).

Also, due to the fact that the respective takeout means (44) are formed in a different level way so as to correspond to the horizontal portion (35) of the supply shute (30), the tension springs S are taken out in such a manner that they are maintained inclined at a predetermined angle.

When the tension springs S are taken out by the takeout mechanism (40) in this manner, then the transfer device (47), which is located so as to correspond to the pushout direction of the takeout means (44) of the takeout mechanism (44), is operated to catch the tension springs S and to transfer them to the seat frame (1) placed and fixed to a tension spring mounting apparatus to be described later. As the transfer device (47), an industrial robot is employed. The industrial robot includes a predetermined number of manipulators (48) and (49) (4 manipulators in the illustrated embodiment) located symmetrically on the mutually 1800 opposing sides of the tip end portion thereof in such a manner that they can correspond to the intervals a, b, c of the engagement holes (6) in the seat frame (1) respectively.These four manipulators (48) and (49) are opened or closed simultaneously by means of operation of cylinders (48a) and (49a). The manipulators (48) and (49) are also provided in the insides of the tip end portion thereof with grab portions (48b) and (49b) which are used to grab the tension spring S therebetween.

Also, the manipulators (48) and (49) are formed in an inclined manner so as to be able to catch in the intersecting direction the tension springs S that are taken out inclined as mentioned above. Further, to one of grip portions of the respective manipulators there is fixed an L-shaped abutment piece (50) such that it is situated upwardly of the grab portions (48b) and (49b). This abutment piece (50) is used to support the upper face of the tension spring S when it is caught so as to be able to maintain the positive catch condition of the tension spring S in the intersecting direction.

In the transfer device (47), each time the tension springs S are taken out by the above-mentioned takeout mechanism (40), one manipulator (48) and the other manipulator (49) are reversed to correspond to the takeout means (44) alternately to catch the corresponding tension springs S out of the tension springs S pushed up by the takeout means (44) so as to transfer and mount the tension springs S to the tension spring mounting device.

Specifically, in order to correspond to the catch by the manipulators (48) and (49), in the illustrated embodiment, as described before, 6 sets of takeout means (44) are arranged and thus 6 tension springs S are to be taklen out by those takeout means (44). One manipulator (48) catches the tension springs S that are taken out by the first takeout means (44a), the third takeout means (44c), the fifth takeout means (44e) and the sixth takeout means (44f) respectively corresponding thereto, and then mounts them to a rear frame (lb) in one half section (a left half section in the illustrated embodiment) of the seat frame (1).On the other hand, the other manipulator (49) catches the tension springs S taken out by the sixth takeout means (44f), the fourth takeout means (44d), the second takeout means (44b) and the first takeout means (44a) respectively corresponding to thereto, and then mounts them to a front frame (la) in the half section of the seat frame (1). In the operation of the transfer device (47), when the tension spring S is caught and lifted up, one end hook Sf of the tension spring S is caused to pass between the two guide wall members (46a)(46b) of a direction restricting means (46) so that the peripheral direction of the tension spring S can be restricted.That is, when the tension spring S is lifted up with the end hook Sf inclined, then the end hook Sf is moved upwardly in sliding contact with the inner surfaces of the guide wall members (46a),(46b), with the result that the tension spring S is rotated in the peripheral direction thereof against the gripping force of the manipulator and thus is rectified into a state in which the tip end of the end hook Sf is allowed to point downward vertically (Fig 9).

After the tension springs S are mounted to the one half section of the seat frame (1) in the above-mentioned way, also in the other half section of the seat frame (1) the tension springs S are mounted symmetrically. That is, in order to mount the tension springs S in the other half section of the seat frame (1), when the manipulators (48) and (49) catch the tension springs S taken out by the takeout mechanism (44) in the above-mentioned manner, the one manipulator (48) and the other manipulator (49) are reversed, so that the tension springs S caught by the one manipulators (48) are mounted to a front frame (la) of the other half section of the seat frame (1) and the tension springs S caught by the other manipulators (49) are mounted to a rear frame (lb) of the other half section of the seat frame (1), respectively.

Downstream of the thus constructed tension spring S takeout mechanism and transfer device, that is, in the next stage thereof, there is arranged a tension spring mounting device (60).

In Figs 10, 11 and 12, there are shown the perspective, longitudinal side section and explanatory views of the tension spring mounting device (60). The tension spring mounting device (60) comprises a positioning/guiding mechanism (62) located in the front and rear portions of the mounting bed (61) for fixation of the seat frame (1) to hold the seat frame (1) as well as to guide the tension springs S, and a pad receive member spread mechanism (63) disposed midway of the seat frame mounting bed (61).

The positioning/guide mechanism (62) includes a clamp member (64) for holding the seat frame (1) and guide means (65) for guiding the tension springs S to the seat frame (1). The clamp member (64) is mounted by means of a shaft (68) to a bearing (67) erected outside and correspondingly to a mounting block (66) in the two ends of which the front frame (la) and rear frame (lb) of the seat frame (1) are placed or mounted respectively, so that the clamp member (64) is allowed to rise and fall as required toward the upper face side of the mounting block (66). The inner end portion of the clamp member (64) is curved in an L-shaped configuration to provide an engagement portion (64a) which in turn cooperate with an engagement stepped surface (66a) formed on the upper surface of the mounting block (66) to define a grasping space portion.Also, the outer end portion of the clamp member (64) is connected to a cylinder (69) provided in the mounting bed (61) so that the outer end portion is allowed to rise and fall by means of operation of the cylinder (69).

There are arranged two such clamp members (64) for the seat frame (1) on the mounting bed (61) in such a manner that they are respectively located correspondingly to the two ends of the front and rear portions of the seat frame (1). Between and to the two clamp members (64) there is fixed a support member (70) which is provided with a plurality of guide means (65) respectively extending in a direction intersecting with the clamp members (64) and located correspondingly to the engagement holes (6) in the seat frame (1).

Each of the guide means (65) comprises a pair of mutually opposing guide wall members (65a)(65b) and an inner wall member (65c). The clearance between the two guide wall members (65a)(65b) is defined slightly greater than the diameter of the tension spring to provide a restricting surface of the tension springs S in the peripheral direction thereof. Also, the inner wall (65c) of the guide means (65) serves as a restricting surface of the tension springs S in the longitudinal direction thereof.

In the positioning/guiding mechanism (62) constructed in this manner, when the seat frame (1) is set onto the mounting bed (61), the clamp member (64) is kept in the standup position thereof, and the cylinder (69) is operated after the seat frame (1) is set onto the mounting block (66) of the mounting bed (61). The operation of the cylinder (69) causes the clamp member (64) to rotate and fall downward, so that the front and rear frames (la) and (lb) of the seat frame (1) are pressed and held by and between the engagement portion (64a) of the clamp member (64) and the engaged stepped surface (66a) of the mounting block (66), that is, are fixedly held therebetween.At the same time, during the standup condition of the clamp member (64), the guide means (65) lying horizontally are made to correspond substantially perpendicularly to the engagement holes (6), respectively, with the rotational movements of the clamp members (64).

The pad receive member spread mechanisms (63) includes a plurality of (in the illustrated embodiment, 3) tension arms (73) which are disposed in the front portion of the mounting bed (61) such that they can be moved by cylinders (not shown) in the inward and outward direction of the mounting bed (61), that is, in a direction approaching the front frame (la) of the seat frame (1) to be mounted and fixed to the mounting bed (61), and a plurality of (in the illustrated embodiment, 3) fixed arms (74) fixed to the rear portion of the mounting bed (61), that is, the portion of the mounting bed (61) adjacent to the rear frame (lb) of the seat frame (1). The respective arms (73)(74) are provided with cutaway engagement portions (73a)(74a) which are located in the outside portions of the tip ends thereof.

In the thus constructed pad receive member spread mechanism (63), in a state in which the tension arms (73) are moved inwardly, the pad receive member (5) is held between the two kinds of arms (73)(74) by bringing the two side members (2a) and (2b) into engagement with the engagement portions (73a) of the tension arms (73) and the engagement portions (74a) of the fixed arms (74), respectively. With this state maintained, the tension arms (73) are moved outwardly by means of operation of the cylinders (not shown) to thereby pull in the side member (2a) of the pad receive member (5) toward the front frame (la) to make the pad receive member (5) tensioned, while the pad receive member (5) is set at such an interval from the front frame (la) that the tension springs S can be mounted between the pad receive member (5) and the front frame (la) of the seat frame (1).

In this manner, the tension springs S can be mounted between the seat frame (1) placed and fixed onto the mounting bed (61) and the pad receive member (5) spread and held in the central portion of the seat frame (1). In order to mount the tension springs S, as described before, the four tension springs S that have been delivered from the horizontal portion (35) of the supply shute (30) by the transfer device (47) are lowered down vertically from above the guide means (65), respectively, the one-side end hooks Sf of the tension springs S are inserted into the engagement holes (6) of the seat frame (1), and the otherside end hooks Sf are engaged with the side members (2a) and (2b) of the pad receive member (5), so that the four tension springs S can be mounted simultaneously.

In this mounting operation, when passing through the guide means (65), the one-side end hooks Sf of the tension springs S are respectively restricted in the peripheral direction thereof beween the respective guide walls (65a)(65b) and thus the inclination of these end hooks Sf is rectified, while the respective outer end edges of these end hooks Sf are pressed against the respective inner walls (65c) of the guide means (65) from the inclined portions (65d) thereof to move the tension springs S in the longitudinal direction thereof against the gripping forces of the respective manipulators (48)(49), whereby the longitudinal direction of each of the tension springs S is restricted or rectified.As a result of this, with the dimensional variations of the individual tension springs S being absorbed, the end hooks Sf of the respective tension spings S can be guided and inserted into the engagement holes (6) in the seat frame (1), respectively.

In this insertion of the end hooks Sf of the tension springs S into the engagement holes (6) in the seat frame (1), as discussed before, since each of the tension springs S is transferred in an inclined manner for mounting, the arc-like curved tip end of the end hook Sf is directed in a direction easy to insert into its associated engagement hole (6), so that the end hook Sf can be inserted into the engagement hole (6) smoothly.

As mentioned above, due to the fact that, in mounting the tension springs S, the end hooks Sf thereof are guided into their associated engagement holes (6) by the guide means (65), respectively, a plurality of tension springs S can be mounted simultaneously and smoothly to thereby reduce the time for mounting thereof.

After the tension springs S are mounted to the seat frame (1) in the above-mentioned manner, the transfer device (47) returns to its initial position and the tension arms (73) of the pad receive member spread mechanism (63) are moved inwardly, thereby removing the tension of the pad receive. members (5). As a result of this, the pad receive members (5) are resiliently spread and supported relative to the seat frame (1) only by the tension springs S.

The foregoing operations complete the spreading of the pad receive members (5) to the seat frame (1).

As has been described hereinbefore, according to the tension spring takeout device in a tension spring automatic mounting apparatus according to the invention, since a predetermined number of tension springs can be taken out and mounted to the frame members automatically, the operation time for mounting the tension springs can be reduced greatly when compared with the conventional automatic tension spring mounting apparatus, which enhances the working efficiently remarkably.

Claims (10)

1. An automatic tension spring mounting device in which a plurality of tension springs each having two end hooks at the two ends thereof are caught simultaneously by a transfer device and said end hooks are then mounted in engagement portions formed in a seat frame, respectively, said automatic tension spring mounting device comprising: two identical positioning/guiding mechanisms respectively disposed in the front and rear portions of a mounting bed, to which said seat frame is to be fixedly mounted, for holding said seat frame and for guiding said tension springs towards said engagement portions; and, one or more identical pad receive member spread mechanisms respectively interposed between said front and rear positioning/guiding mechanisms.

2. An automatic tension spring mounting device according to Claim 1 in which each of said two positioning/guiding mechanisms includes two clamp members for holding said seat frame and a plurality of guide means for guiding said tension springs towards said engagement portions of said seat frame.

3. An automatic tension spring mounting device according to Claim 2 in which each of said four clamp members is mounted via a shaft to a bearing erected outside of a corresponding one of four support blocks on which the end portions of the front and rear frames of said seat frame are respectively placed in such a manner that said clamp member can be raised and lowered correspondingly to the upper surface of said support block, each of said four clamp members includes an inner end portion which is bent in an L-shaped manner to provide an engagement portion, each of said four support blocks is provided with a stepped engagement surface on the upper surface side thereof, said L-shaped engagement portion of said clamp member being cooper able with said stepped engagement portion of said support block to provide a grasping space portion therebetween, and each of said four clamp members includes an outer end portion connected to a cylinder provided in said mounting bed, said outer end portion of said clamp member being raisable and lowerable by means of operation of said cylinder.

4. An automatic tension spring mounting device according to Claim 2 or Claim 3 in which said guide means are respectively located at such positions as correspond to said engagement portions formed in said seat frame and are adapted to be able to restrict said tension springs in the peripheral and longitudinal directions thereof, whereby said end hooks of said tension springs can be guided into said engagement portions in said seat frame by said guide means, respectively.

5. An automatic tension spring mounting device according to any of Claims 2 to 4 in which between said four clamp members disposed correspondingly to the end portions of said front and rear portions of said seat frame fixedly mounted on said mounting bed, there are provided four support members extending between and fixed to said clamp members, two of said support members being located between said clamp members disposed correspondingly to said two end portions of said front portion of said seat frame, the remaining two of said support members being located between said clamp members disposed correspondingly to said two end portions of said rear portion of said seat frame, and also wherein each of said support members is provided with a plurality of guide means extending in a direction intersecting with said clamp members and located so as to correspond respectively to their associated engagement bores formed in said seat frame.

6. An automatic tension spring mounting device according to any of Claims 2 to 5 in which each of said guide means is composed of a pair of mutually opposed guide side walls and an inner wall, said two guide side walls are spaced at a distance from each other slightly greater than the diameters of said tension springs to provide a restricting surface for restricting said tension spring in the peripheral direction thereof, said inner wall of said guide means acts as a restricting surface for restricting said tension spring in the longitudinal direction thereof, and said inner wall is provided with an inclined portion in the upper portion thereof.

7. An automatic tension spring mounting device according to any of Claims 2 to 6 in which each of said guide means is formed of a pair of guide piece members and a plate-like bracket fixed to said support member in such a manner that said pair of guide piece members are disposed respectively on the two sides of said plate-like bracket to grasp it therebetween and are then mounted thereto in a manner to extend in a direction intersecting with said clamp member, the inner surfaces of said guide piece members are respectively used as said guide side walls, the inner edge portion of said plate-like bracket is used as said inner wall, and the upper portion of said inner edge portion of said plate-like bracket is inclined to provide said inclined surface.

8. An automatic tension spring mounting device according to any of the preceding Claims in which one of said two pad receive member spread mechanisms comprises a plurality of tension arms disposed in the forward portion of said mounting bed and movable by a cylinder inwardly and outwardly of said mounting bed, that is, in a direction approaching said front frame of said seat frame to be fixed to said mounting bed, and a plurality of fixed arms to be fixed to the rearward portion of said mounting bed adjacent to said rear frame of said seat frame, each of said tension and fixed arms being formed with a cutaway engagement portion in the outer portion of the tip end portion thereof.

9. An automatic tension spring mounting device according to Claim 1 and substantially as herein described.

10. An automatic tension spring mounting device substantially as herein described with reference to the accompanying drawings.